Red Hat Linux Linux Kernel Vulnerabilities & Security Advisories
2148 advisories tracked · Red Hat Security Data API · 1 listed in the CISA Known Exploited Vulnerabilities catalog
Every row below is a published Red Hat Linux advisory that VulniPulse classified as Linux Kernel, with the CVEs, affected and fixed releases and exploitation status the vendor stated. Severity mix: 781 high, 1364 medium, 1 low.
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Latest Red Hat Linux Kernel advisories
High [CVE-2026-68156] refresh auth->authorizer_buf{,_len} after authorizer update
In the Linux kernel, the following vulnerability has been resolved: libceph: refresh auth->authorizer_buf{,_len} after authorizer update ceph_x_create_authorizer() caches au->buf->vec.iov_base and au->buf->vec.iov_len in struct ceph_auth_handshake. These cached values are then used by the messenger connect code when sending the authorizer. ceph_x_update_authorizer() can rebuild the authorizer when a newer service ticket is available. If the rebuilt authorizer no longer fits in the existing buffer, ceph_x_build_authorizer() drops its reference to au->buf and allocates a new one. If this is the final reference, ceph_buffer_put() frees the old ceph_buffer and its vec.iov_base, but auth->authorizer_buf still points at that freed memory. A subsequent msgr1 reconnect can therefore queue the stale pointer and trigger a KASAN slab-use-after-free in _copy_from_iter() while tcp_sendmsg() copies the authorizer. Refresh auth->authorizer_buf and auth->authorizer_buf_len after a successful authorizer rebuild so the messenger sends the current buffer. During an authorizer update, if the authorizer is rebuilt, a stale pointer to a freed memory region can be retained. A remote attacker could exploit this by triggering a specific network reconnection, leading to a use-after-free vulnerability. This memory corruption could result in a system crash or denial of service.
High [CVE-2026-68155] Linux kernel (libceph): Denial of Service due to malformed monitor maps
In the Linux kernel, the following vulnerability has been resolved: libceph: Reject monmaps advertising zero monitors A message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a monitor to the client. This monmap contains information about the existing monitors in the cluster. Currently, a monmap indicating that there are zero monitors in the cluster is treated as valid. Therefore, such a monmap must be corrupted and should be treated as invalid. Furthermore, a monmap with a monitor count of zero can subsequently crash the client when attempting to open a session with a monitor in __open_session(). This happens because the "BUG_ON(monc->monmap->num_mon CEPH_MAX_MON. [ idryomov: drop "log output for unusual values of num_mon" part ] A remote attacker could send a specially crafted monitor map (monmap) that advertises zero monitors. This vulnerability results in a Denial of Service (DoS) for the client. Red Hat severity: Moderate — CVSS 7.1 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H). Weakness: CWE-617. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 8. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
High [CVE-2026-68154] reject zero bucket types in crush_decode
In the Linux kernel, the following vulnerability has been resolved: libceph: reject zero bucket types in crush_decode CRUSH bucket type 0 is reserved for devices. The mapper relies on that invariant and uses type 0 to identify leaf devices. If crush_decode() accepts a bucket with type 0, a malformed CRUSH map can make the mapper treat a negative bucket ID as a device and pass it to is_out(), which then indexes the OSD weight array with a negative value. Reject zero bucket types while decoding the CRUSH map so the invalid state never reaches the mapper. A remote attacker could provide a specially crafted CRUSH map with a zero bucket type. This could result in a denial of service. Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-125. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat OpenShift Container Platform 4. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
High [CVE-2026-68149] preserve ACL_DONT_CACHE state in forget_cached_acl
In the Linux kernel, the following vulnerability has been resolved: fs: preserve ACL_DONT_CACHE state in forget_cached_acl() The ACL_DONT_CACHE state is meant to be a constant state for the inode for filesystems that want to opt out of posix acl caching. Commit facd61053cff1 ("fuse: fixes after adapting to new posix acl api") used this facility to opt out of posix acl caching for fuse inodes with fuse server that does not negotiate FUSE_POSIX_ACL (fc->posix_acl). The commit also takes care to gate the forget_all_cached_acls() call in fuse_set_acl() on fc->posix_acl because there is no need for it, but there are other placed in fuse code which call forget_all_cached_acls() unconditional to fc->posix_acl and those cause the loss of the ACL_DONT_CACHE state. This is not only a functional bug. Properly timed, a get_acl() from this fuse filesystem can return a stale cached value, as was observed in tests, because set_acl() does not invalidate the unintentional acl cache. We could fix this in fuse, but it actually makes no sense for the vfs helper forget_cached_acl() to invalidate the ACL_DONT_CACHE state, so let it not do that to fix fuse and future users of ACL_DONT_CACHE. The `forget_cached_acl()` helper function, intended to manage Access Control List (ACL) caching, incorrectly invalidates the `ACL_DONT_CACHE` state.
High [CVE-2026-68148] Add missing superblock check in find_or_insert_direct_key
In the Linux kernel, the following vulnerability has been resolved: fscrypt: Add missing superblock check in find_or_insert_direct_key() The legacy 'fscrypt_direct_keys' table caches master keys that are used by v1 encryption policies that have FSCRYPT_POLICY_FLAG_DIRECT_KEY. It's just a global table for all filesystems (since the keys can be provided by the legacy process-subscribed keyrings mechanism, which makes it difficult to reuse super_block::s_master_keys). The entries in it ('struct fscrypt_direct_key') do contain a super_block pointer, though, for passing to fscrypt_destroy_inline_crypt_key() when the last inode that references the key is evicted. However, when finding the fscrypt_direct_key for an inode, we weren't actually comparing the super_block pointer. As a result, inodes with different super_blocks could point to the same fscrypt_direct_key. That could extend the lifetime of a fscrypt_direct_key beyond the super_block it points to, causing a use-after-free later. Fix this by creating distinct fscrypt_direct_key structs for distinct super_block structs. Note that this problem doesn't exist in the v2 policy equivalent ("per-mode keys"), since the data structures there are per super_block. A missing superblock check in the `find_or_insert_direct_key()` function could allow inodes from different filesystems to incorrectly share encryption keys.
High [CVE-2026-68145] fix out-of-bounds bitmap_set with zero-length range
In the Linux kernel, the following vulnerability has been resolved: iomap: fix out-of-bounds bitmap_set() with zero-length range ifs_set_range_dirty() and ifs_set_range_uptodate() compute last_blk as (off + len - 1) >> i_blkbits. When off is 0 and len is 0, the unsigned subtraction underflows to SIZE_MAX, producing a huge last_blk and nr_blks value that causes bitmap_set() to write far beyond the ifs->state allocation. Regarding ifs_set_range_uptodate(), it is temporarily safe because len cannot be passed in as 0. However, for ifs_set_range_dirty() this is reachable from __iomap_write_end(): when copy_folio_from_iter_atomic() returns 0 (e.g. user buffer fault) and the folio is already uptodate, the guard at the top of __iomap_write_end() does not trigger because!folio_test_uptodate() is false, and iomap_set_range_dirty() is called with copied == 0. Add a!len guard to both functions before the computation, so that a zero-length range is a no-op. An unsigned subtraction underflow occurs when `ifs_set_range_dirty()` or `ifs_set_range_uptodate()` are called with a zero-length range. This can lead to an out-of-bounds write via `bitmap_set()`, potentially allowing a local attacker to cause memory corruption or a denial of service. Red Hat severity: Important — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-787.
High [CVE-2026-68143] Linux kernel SLIP: Out-of-bounds write due to race condition during MTU change
In the Linux kernel, the following vulnerability has been resolved: net: slip: serialize receive against buffer reallocation sl_realloc_bufs() replaces rbuff and updates buffsize while holding sl->lock. slip_receive_buf() reads those fields and writes through rbuff without holding the lock. An MTU change can therefore race with receive processing. An MTU shrink can expose the new smaller rbuff with the old larger bound, causing an out-of-bounds write. A receive callback which already loaded the old rbuff can instead continue writing after that buffer has been freed. A flaw was found in the Linux kernel's SLIP (Serial Line Internet Protocol) network component. A race condition exists during an MTU (Maximum Transmission Unit) change when the system reallocates receive buffers. This can allow a remote attacker to trigger an out-of-bounds write or write to a freed memory region, potentially leading to a denial of service or arbitrary code execution. Red Hat severity: Important — CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-787. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
High [CVE-2026-68142] require CAP_NET_ADMIN in the device netns for changelink
In the Linux kernel, the following vulnerability has been resolved: geneve: require CAP_NET_ADMIN in the device netns for changelink A tunnel changelink() operates on at most two netns, dev_net(dev) and the sticky underlay netns geneve->net. They differ once the device is created in or moved to a netns other than the one the request runs in. The rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a caller privileged there but not in geneve->net can rewrite a geneve device whose underlay lives in geneve->net. geneve_changelink() applies the new configuration against geneve->net: geneve_link_config() and the geneve_quiesce()/geneve_unquiesce() pair reopen the underlay sockets in that netns (geneve_sock_add() uses geneve->net), so the same reasoning as the tunnel changelink series applies here. Gate geneve_changelink() with rtnl_dev_link_net_capable(), at the top of the op before any attribute is parsed, matching ipgre_changelink() and the rest of the "require CAP_NET_ADMIN in the device netns for changelink" series. Found by 0sec automated security-research tooling ( ). A local attacker, with `CAP_NET_ADMIN` privileges in a specific network namespace, could bypass intended permission checks.
High [CVE-2026-68140] fix use-after-free of a severed iucv_path
In the Linux kernel, the following vulnerability has been resolved: net/iucv: fix use-after-free of a severed iucv_path af_iucv queues not-yet-received message notifications on iucv->message_q, each holding a raw pointer to the connection's iucv_path. When the peer severs the connection, iucv_sever_path() frees that path with iucv_path_free() but leaves the notifications queued. A later recvmsg() drains message_q via iucv_process_message_q() and hands the stale path to message_receive() -- a use-after-free of the freed iucv_path. Drop the queued notifications when the path is severed; once the path is gone they can no longer be received. This also frees the notifications leaked when a socket is closed with messages still queued. When a peer severs a connection, message notifications that still reference the freed connection path remain in a queue. A subsequent attempt to process these stale notifications can lead to memory corruption, potentially resulting in a system crash (denial of service) or allowing an attacker to execute arbitrary code. Red Hat severity: Important — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-825. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat OpenShift Container Platform 4.
High [CVE-2026-68138] serialize qdisc_rtab_list against concurrent get/put
In the Linux kernel, the following vulnerability has been resolved: net/sched: serialize qdisc_rtab_list against concurrent get/put qdisc_get_rtab() and qdisc_put_rtab() mutate the process-global singly linked list qdisc_rtab_list and a plain non-atomic 'int refcnt' with no lock. This was only safe because every caller historically held the RTNL mutex, which serialized all rate-table lookups, inserts and frees. That invariant no longer holds. cls_flower sets TCF_PROTO_OPS_DOIT_UNLOCKED, so tc_new_tfilter() keeps rtnl_held == false for it and sets TCA_ACT_FLAGS_NO_RTNL. That flag propagates through tcf_exts_validate_ex() -> tcf_action_init() -> tcf_action_init_1() -> tcf_police_init(), which calls qdisc_get_rtab()/qdisc_put_rtab() with the RTNL mutex NOT held. Two RTM_NEWTFILTER requests on different CPUs, each adding a flower filter with a police action carrying the same rate, then race on qdisc_rtab_list and on the non-atomic refcnt, leading to a use-after-free / double-free of the kmalloc-2k struct qdisc_rate_table. qdisc_rtab_list is a single global (not per-netns), so the corrupted object is shared system-wide. Affected products named by the advisory: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Enterprise Linux for NVIDIA 26; and 1 more.
High [CVE-2026-68136] fix double aggregation of flush-marked skbs
In the Linux kernel, the following vulnerability has been resolved: net: gro: fix double aggregation of flush-marked skbs Commit 0ab03f353d36 ("net-gro: Fix GRO flush when receiving a GSO packet.") added a flush check to skb_gro_receive(), but skb_gro_receive_list() lacks the same validation. As a result, packets marked with NAPI_GRO_CB(skb)->flush may still be re-aggregated. This allows already-GRO'd packets with existing frag_list to be re-aggregated into a new GRO session, corrupting the frag_list chain structure. When skb_segment() attempts to unpack these malformed packets, it encounters invalid state and triggers a kernel panic. Scenario (Tethering/Device forwarding): 1. Driver: Generated aggregated packet P1 via LRO with frag_list 2. Dev A: Receives aggregated fraglist packet and flush flag set 3. Dev A: Re-enters GRO, skb_gro_receive_list() is called 4. Missing flush check allows re-aggregation despite flush flag 5. Frag_list chain becomes corrupted (loops or dangling refs) 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list Root cause in skb_segment(): The check at line ~4891: if (hsize = nfrags && skb_headlen(list_skb) && (skb_headlen(list_skb) == len || sg)) { When frag_list is corrupted by double aggregation, when list_skb is a NULL pointer from skb->next, skb_headlen(list_skb) dereference NULL/corrupted pointers occurs.
High [CVE-2026-68131] Reset positive result codes to zero in object map update path
In the Linux kernel, the following vulnerability has been resolved: rbd: Reset positive result codes to zero in object map update path In a reply message to an RBD request, a positive result code indicates a data payload, which is not allowed for writes. This happens, because rbd_object_map_callback() calls rbd_obj_handle_request() -> __rbd_obj_handle_request() and passes this positive result code. From __rbd_obj_handle_request(), rbd_obj_advance_write() is called, which leaves the positive result code unchanged and returns true. Therefore, the if(done && *result) branch is executed in __rbd_obj_handle_request() and the assertion triggers. This patch fixes the issue by adjusting the logic in the rbd_object_map_callback() path. A positive result code for an object map update is now reset to zero (similar to rbd_osd_req_callback()), and the message is subsequently handled the same way as if the result code was zero from the beginning. Additionally, a WARN_ON_ONCE() is added for this case. A corrupted reply to an object map update can cause the `rbd_object_map_callback()` function to process a positive result code, which is not allowed for write operations. This incorrect handling triggers an assertion in `__rbd_obj_handle_request()`, leading to a system crash and a Denial of Service (DoS). Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H).
High [CVE-2026-68128] Linux kernel (ice): Denial of Service via out-of-range ptype in VIRTCHNL
In the Linux kernel, the following vulnerability has been resolved: ice: reject out-of-range ptype in ice_parser_profile_init set_bit(rslt->ptype, prof->ptypes) operates on a DECLARE_BITMAP of ICE_FLOW_PTYPE_MAX (1024) bits. Nothing prevents a malicious VF from providing ptype >= 1024 through VIRTCHNL, resulting in a write past the end of the bitmap and a kernel page fault. Reproduced with a custom kernel module injecting a crafted VIRTCHNL_OP_ADD_RSS_CFG on E810-C QSFP (8086:1592), FW 4.91 0x800214af 1.3909.0, ICE COMMS DDP 1.3.53.0, kernel 7.1.0-rc1. crash_parser: ice_parser_profile_init @ ffffffffc0d61b60 crash_parser: setting ptype=0xffff (max valid=1023) crash_parser: calling ice_parser_profile_init -- expect OOB crash! BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: Oops: 0002 [#1] SMP NOPTI CPU: 56 UID: 0 PID: 165011 Comm: insmod Kdump: loaded Tainted: G S U OE 7.1.0-rc1 #1 Hardware name: Intel Corporation S2600BPB/S2600BPB RIP: 0010:ice_parser_profile_init+0x2d/0x1d0 [ice] Call Trace:? __pfx_ice_parser_profile_init+0x10/0x10 [ice] crash_init+0x127/0xff0 [crash_parser] do_one_initcall+0x45/0x310 do_init_module+0x64/0x270 init_module_from_file+0xcc/0xf0 idempotent_init_module+0x17b/0x280 __x64_sys_finit_module+0x6e/0xe0 Bail out early with -EINVAL when ptype is out of range.
High [CVE-2026-68125] reject frames shorter than the authentication tag
In the Linux kernel, the following vulnerability has been resolved: mac802154: llsec: reject frames shorter than the authentication tag llsec_do_decrypt_auth() computes the associated-data length for the AEAD request as assoclen += datalen - authlen; where datalen is the number of bytes after the MAC header and authlen (4, 8 or 16) is the length of the authentication tag. Nothing verifies that the frame actually carries at least authlen payload bytes. A secured frame whose payload is shorter than the tag makes datalen - authlen negative; assoclen is then passed to aead_request_set_ad() as an unsigned value close to 4 GiB, so crypto_aead_decrypt() walks far off the end of the scatterlist that only spans the real frame. The frame is fully attacker-controlled and reaches this path from any IEEE 802.15.4 peer in radio range. Dynamically reproduced on a KASAN kernel as a general-protection-fault in the AEAD scatterwalk, and the fix confirmed. A remote attacker, within radio range, could send a specially crafted IEEE 802.15.4 frame with a payload shorter than its authentication tag. This incorrect frame processing can lead to an out-of-bounds read during cryptographic operations, causing a general-protection fault and resulting in a denial of service (DoS). Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-125.
High [CVE-2026-68121] Linux kernel: PPPoE memory corruption via stale pointer
In the Linux kernel, the following vulnerability has been resolved: pppoe: reload header pointer after dev_hard_header() pppoe_sendmsg() saves a pointer to the PPPoE header before calling dev_hard_header(). Device header callbacks are allowed to reallocate the skb head, invalidating pointers into it. This can happen when a send is blocked in copy_from_user() while the first non-Ethernet port is added to an empty team device. The team's delegated GRE header callback then expands the skb head. PPPoE subsequently writes six bytes through the stale pointer into the freed head. Reload the PPPoE header through the skb's network-header offset after device header creation. pskb_expand_head() updates that offset when it relocates the head. A flaw was found in the Linux kernel's PPPoE (Point-to-Point Protocol over Ethernet) implementation. This vulnerability occurs because a pointer to network packet data is not updated after memory is reallocated, leading to the use of an outdated memory address. An attacker with local access could potentially trigger this condition, causing memory corruption. This could result in a system crash (denial of service) or other unpredictable system behavior. Red Hat severity: Moderate — CVSS 7.3 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H). Weakness: CWE-825.
High [CVE-2026-68118] challenge ACK for non-exact RST in SYN-RECEIVED
In the Linux kernel, the following vulnerability has been resolved: tcp: challenge ACK for non-exact RST in SYN-RECEIVED The SYN-RECEIVED request-socket path in tcp_check_req() accepts an in-window RST without requiring SEG.SEQ to exactly match RCV.NXT. RFC 9293 section 3.10.7.4 applies the RFC 5961 reset check in SYN-RECEIVED: an exact RST resets the connection, while a non-exact in-window RST must trigger a challenge ACK and be dropped. Apply that check before the ACK-field validation, following the RFC sequence-number, RST, then ACK processing order. Factor the per-netns challenge ACK quota out of tcp_send_challenge_ack() so request sockets can share it. Use the request socket's send_ack() callback and its own out-of-window ACK timestamp to send and rate-limit the response. A flaw was found in the Linux kernel's handling of TCP (Transmission Control Protocol) connections. A remote attacker could send a specially crafted TCP Reset (RST) packet during the SYN-RECEIVED state. This could cause the system to prematurely remove connection requests instead of issuing a challenge acknowledgment (ACK), potentially leading to a denial of service (DoS) by disrupting the establishment of new network connections. Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-358.
High [CVE-2026-68108] fix integer overflow in image size
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vce: fix integer overflow in image size Fix a security vulnerability where malicious VCE command streams with oversized dimensions (e.g. 65536×65536) cause 32-bit integer overflow, wrapping the calculated buffer size to 0. This bypasses validation and allows GPU firmware to perform out-of-bound memory access. The fix uses 64-bit arithmetic to detect overflow and rejects invalid dimensions before they reach the hardware. V2: remove redundant check V3: modify max height value V4: remove size64 (cherry picked from commit cbe408dba581755ad1279a487ec786d8927d778d) Malicious VCE (Video Codec Engine) command streams with oversized dimensions can cause a 32-bit integer overflow. This could lead to system instability or potentially arbitrary code execution. Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-787. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat OpenShift Container Platform 4. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
High [CVE-2026-68100] validate num_subauth when copying ACE in set_ntacl_dacl
In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate num_subauth when copying ACE in set_ntacl_dacl set_ntacl_dacl() copies each ACE from the attacker-controlled stored security descriptor verbatim into the response DACL without checking sid.num_subauth. The ACE bytes (including an unchecked num_subauth) originate from an authenticated SMB2_SET_INFO(SecInfo=DACL) that is stored raw via ksmbd_vfs_set_sd_xattr(); parse_dacl() rejects a bad ACE with `break` rather than an error, so parse_sec_desc() still returns success and the malformed SD reaches the xattr intact. On a subsequent SMB2_QUERY_INFO(SecInfo=DACL) for an inode carrying a POSIX access ACL, build_sec_desc() -> set_ntacl_dacl() -> set_posix_acl_entries_dacl() walks the copied ACEs and reads ntace->sid.sub_auth[ntace->sid.num_subauth - 1] with num_subauth taken straight from the stored SD. Since sub_auth[] is fixed at SID_MAX_SUB_AUTHORITIES (15), a crafted num_subauth (e.g. 255) drives an out-of-bounds heap read of ~1 KB with an offset fully controlled by an authenticated client. The sibling functions already gate this field: parse_dacl() -- num_subauth == 0 || > SID_MAX_SUB_AUTHORITIES parse_sid() -- num_subauth > SID_MAX_SUB_AUTHORITIES smb_copy_sid() -- min_t(u8, num_subauth, SID_MAX_SUB_AUTHORITIES) set_ntacl_dacl() is the lone inconsistent path that omits the check.
High [CVE-2026-68093] Bump asid_generation on CPU online to avoid ASID collision after hotplug
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Bump asid_generation on CPU online to avoid ASID collision after hotplug If a vCPU stays scheduled out (or blocked) while the last pCPU it ran on goes through a hotplug cycle (online->offline->online), and the vCPU then resumes execution on the same pCPU, then it is possible for it to run with an ASID that has now been assigned to a different vCPU, resulting in stale TLB translations being used. svm_enable_virtualization_cpu() resets asid_generation to 1 and sets next_asid to max_asid + 1 on every CPU online event, including hotplug cycles. Because next_asid starts beyond the pool boundary, the first call to new_asid() after an online event always wraps the pool, incrementing asid_generation to 2 and assigning ASIDs starting from min_asid. Consider two vCPUs from different VMs, vCPU-A pinned to CPU-X holding asid_generation=2 and ASID=N from before the hotplug event: 1. 2. One or more vCPUs migrate to CPU-X and call new_asid(), wrapping the pool and consuming ASIDs starting from min_asid. 3. vCPU-A enters pre_svm_run() on CPU-X: current_vmcb->cpu is unchanged so the migration branch is skipped. Its saved asid_generation=2 matches sd->asid_generation=2, so the generation check silently passes and vCPU-A continues running with ASID=N — the same ASID just freshly assigned to vCPU-B.
High [CVE-2026-68388] handle overlapping allocated ranges in fallocate
In the Linux kernel, the following vulnerability has been resolved: smb/client: handle overlapping allocated ranges in fallocate smb3_simple_fallocate_range() can skip holes when an allocated range returned by the server starts before the current fallocate offset. The skipped hole is not zero-filled, but fallocate still returns success. A later write to that hole may therefore fail with ENOSPC. The function queries allocated ranges so that it can preserve existing contents and write zeroes only into holes. For example, assume the fallocate request is [100, 400) and the only allocated range returned by the server is [0, 200): Request: [100, 400) Server range: [ 0, 200) allocated Correct: [100, 200) allocated data, skip [200, 400) hole, zero-fill Current: [100, 300) skipped [300, 400) zero-filled afterwards The current code adds the full server range length, 200, to the current offset 100 and moves to 300. Ignore ranges that end before the current offset and reject ranges whose end offset overflows. This also prevents a malformed range length from causing an out-of-bounds zero-buffer read. The `smb3_simple_fallocate_range()` function, which manages file allocation, can incorrectly process overlapping allocated ranges provided by a server. This can result in parts of a file not being properly zero-filled, leading to potential data integrity issues.