Red Hat Linux Red Hat Enterprise Linux Vulnerabilities & Security Advisories
1225 advisories tracked · Red Hat Security Data API · 3 listed in the CISA Known Exploited Vulnerabilities catalog
Every row below is a published Red Hat Linux advisory that VulniPulse classified as Red Hat Enterprise Linux, with the CVEs, affected and fixed releases and exploitation status the vendor stated. Severity mix: 31 critical, 785 high, 384 medium, 25 low.
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Latest Linux Red Hat Enterprise Linux advisories
High [CVE-2026-53236] restrict SO_ATTACH_FILTER to priv users
In the Linux kernel, the following vulnerability has been resolved: tcp: restrict SO_ATTACH_FILTER to priv users This patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets to users with CAP_NET_ADMIN capability. This blocks potential side-channel attack where an unprivileged application attaches a filter to leak TCP sequence/acknowledgment numbers. An unprivileged application can exploit this vulnerability by attaching a Berkeley Packet Filter (BPF) using the SO_ATTACH_FILTER option. This allows the application to conduct a side-channel attack, leading to the leakage of sensitive TCP sequence and acknowledgment numbers. This information disclosure could potentially be used to aid further attacks. 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-266. 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. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53242] Fix wait queue list corruption in snd_pcm_drain on linked streams
In the Linux kernel, the following vulnerability has been resolved: ALSA: PCM: Fix wait queue list corruption in snd_pcm_drain() on linked streams snd_pcm_drain() uses init_waitqueue_entry which does not clear entry.prev/next, and add_wait_queue with a conditional remove_wait_queue that is skipped when to_check is no longer in the group after concurrent UNLINK. The orphaned wait entry remains on the unlinked substream sleep queue. On the next drain iteration, add_wait_queue adds the entry to a new queue while still linked on the old one, corrupting both lists. A subsequent wake_up dereferences NULL at the func pointer (mapped from the spinlock at offset 0 of the misinterpreted wait_queue_head_t), causing a kernel panic. Replace init_waitqueue_entry/add_wait_queue/conditional remove_wait_queue with init_wait_entry/prepare_to_wait/ finish_wait. init_wait_entry clears prev/next via INIT_LIST_HEAD on each iteration and sets autoremove_wake_function which auto-removes the entry on wake-up. finish_wait safely handles both the already-removed and still-queued cases. A flaw was found in the Advanced Linux Sound Architecture (ALSA) Pulse-Code Modulation (PCM) component of the Linux kernel. An attacker could exploit this issue to trigger a kernel panic, leading to a Denial of Service (DoS) on the affected system.
High [CVE-2026-53256] hold listener socket in rfcomm_connect_ind
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that lock without taking a reference. rfcomm_connect_ind() then locks the listener, queues a child socket on it, and may notify it after unlocking it. The buggy scenario involves two paths, with each column showing the order within that path: rfcomm_connect_ind(): listener close: 1. Find parent in 1. close() enters rfcomm_get_sock_by_channel() rfcomm_sock_release(). 2. Drop rfcomm_sk_list.lock 2. rfcomm_sock_shutdown() without pinning parent. closes the listener. 3. Call lock_sock(parent) and 3. rfcomm_sock_kill() bt_accept_enqueue(parent, unlinks and puts parent. sk, true). 4. Read parent flags and may 4. parent can be freed. call sk_state_change(). If close wins the race, parent can be freed before rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the deferred-setup callback. After lock_sock() succeeds, recheck that it is still in BT_LISTEN before queueing a child, cache the deferred-setup bit while the parent is locked, and drop the reference after the last parent use.
High [CVE-2026-53218] fix register tracking for F_PRESENT flag
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_exthdr: fix register tracking for F_PRESENT flag nft_exthdr_init() passes user-controlled priv->len to nft_parse_register_store(), which marks that many bytes in the register bitmap as initialized. However, when NFT_EXTHDR_F_PRESENT is set, the eval paths write only 1 byte (nft_reg_store8) or 4 bytes (*dest = 0 on TCP/DCCP error path). When len > 4, registers beyond the first are never written, retaining uninitialized stack data from nft_regs. Bail out if userspace requests too much data when F_PRESENT is set. This vulnerability occurs in the `nft_exthdr` module when handling user-controlled data lengths with a specific flag, `NFT_EXTHDR_F_PRESENT`, enabled. An attacker could exploit this by providing a crafted input, leading to the exposure of uninitialized stack memory. This information disclosure could potentially reveal sensitive system data. 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-824. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53182] reject oversized EMA RNR lists
In the Linux kernel, the following vulnerability has been resolved: wifi: nl80211: reject oversized EMA RNR lists nl80211_parse_rnr_elems() stores the parsed element count in a u8-backed cfg80211_rnr_elems::cnt field and uses that count to size the flexible array allocation. Reject nested NL80211_ATTR_EMA_RNR_ELEMS input once the count reaches 255, before incrementing it again. This keeps the parser aligned with the data structure it fills and matches the existing bound check used by nl80211_parse_mbssid_elems(). The nl80211_parse_rnr_elems() function, responsible for parsing EMA RNR (Enhanced Multiple Access Reduced Neighbor Report) lists, does not properly handle an excessive number of nested NL80211_ATTR_EMA_RNR_ELEMS inputs. This improper input validation could allow a remote attacker to cause a denial of service (DoS) by providing an oversized EMA RNR list, potentially leading to system instability or a crash. 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-770. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53230] Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list
In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list mlx5_query_nic_vport_mac_list() sizes its firmware command buffer using the PF's log_max_current_uc/mc_list capabilities. When querying a VF vport with a larger configured max (via devlink), the firmware response can overflow this buffer: BUG: KASAN: slab-out-of-bounds in mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] Read of size 4 at addr ff1100013ffc8a12 by task kworker/u96:2/385 CPU: 12 UID: 0 PID: 385 Comm: kworker/u96:2 Not tainted 7.0.0-rc6+ #1 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) Workqueue: mlx5_esw_wq esw_vport_change_handler [mlx5_core] Call Trace: dump_stack_lvl+0x69/0xa0 print_report+0x176/0x4e4 kasan_report+0xc8/0x100 mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] esw_update_vport_addr_list+0x2e3/0xda0 [mlx5_core] esw_vport_change_handle_locked+0xa1f/0x1060 [mlx5_core] esw_vport_change_handler+0x6a/0x90 [mlx5_core] process_one_work+0x87f/0x15e0 worker_thread+0x62b/0x1020 kthread+0x375/0x490 ret_from_fork+0x4dc/0x810 ret_from_fork_asm+0x11/0x20 Fix by querying the vport's own HCA caps to size the buffer correctly. Refactor the function to allocate and return the MAC list internally, removing the caller's dependency on knowing the correct max.
High [CVE-2026-53228] reload inner IPv6 header after GSO offloads
In the Linux kernel, the following vulnerability has been resolved: ipv6: sit: reload inner IPv6 header after GSO offloads ipip6_tunnel_xmit() caches the inner IPv6 header pointer at function entry and continues using it after iptunnel_handle_offloads(). For GSO skbs, iptunnel_handle_offloads() calls skb_header_unclone(). When the skb header is cloned, skb_header_unclone() can call pskb_expand_head(), which may move the skb head. The pskb_expand_head() contract requires pointers into the skb header to be reloaded after the call. If the later skb_realloc_headroom() branch is not taken, SIT uses the stale iph6 pointer to read the inner hop limit and DS field. That can read from a freed skb head after the old head's remaining clone is released. Reload iph6 after the offload helper succeeds and before subsequent reads from the inner IPv6 header. Keep the existing reload after skb_realloc_headroom(), since that branch can also replace the skb. A flaw was found in the Linux kernel's Simple Internet Transition (SIT) tunnel driver for IPv6. When processing network traffic with Generic Segmentation Offload (GSO) enabled, the driver may use a stale pointer to the inner IPv6 header after the socket buffer (skb) head has been reallocated. This can lead to reading from freed memory, potentially allowing an attacker to cause a denial of service or gain access to sensitive information.
High [CVE-2026-53185] fix use-after-free in zram_bvec_write_partial
In the Linux kernel, the following vulnerability has been resolved: zram: fix use-after-free in zram_bvec_write_partial() zram_read_page() picks the sync or async backing device read path based on whether the parent bio is NULL. zram_bvec_write_partial() passes its parent bio down, so for ZRAM_WB slots the read is dispatched asynchronously and zram_read_page() returns 0 while the bio is still in flight. The caller then runs memcpy_from_bvec(), zram_write_page() and __free_page() on the buffer, leaving the async read to write into a freed page. zram_bvec_read_partial() was switched to NULL in commit 4e3c87b9421d ("zram: fix synchronous reads") for the same reason; the write_partial counterpart was missed. A flaw was found in the Linux kernel, specifically within the zram module. This vulnerability is a use-after-free error, where the system attempts to use a piece of memory after it has been freed. This occurs when the `zram_bvec_write_partial()` function allows an asynchronous read to write into a page that has already been deallocated. Such a flaw can lead to system instability, causing crashes, or in some scenarios, could be exploited by a local attacker to escalate privileges or execute arbitrary code. The function can return while the read bio is still in flight, after which the caller updates the temporary page, writes it back, and frees it.
High [CVE-2026-53249] restrict IPOPT_SSRR and IPOPT_LSRR options
In the Linux kernel, the following vulnerability has been resolved: ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options This patch restricts setting Loose Source and Record Route (LSRR) and Strict Source and Record Route (SSRR) IP options to users with CAP_NET_RAW capability. This prevents unprivileged applications from forcing packets to route through attacker-controlled nodes to leak TCP ISN and possibly other protocol information. While LSRR and SSRR are commonly filtered in many network environments, they may still be supported and forwarded along some network paths. RFC 7126 (Recommendations on Filtering of IPv4 Packets Containing IPv4 Options) recommend to drop these options in 4.3 and 4.4. A flaw was found in the Linux kernel's IPv4 networking component. 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-266. 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. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53193] Forcibly close timer instances at closing
In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Forcibly close timer instances at closing When snd_timer object is freed via snd_timer_free() and still pending snd_timer_instance objects are assigned to the timer object, it tries to unlink all instances and just set NULL to each ti->timer, then releases the resources immediately. The problem is, however, when there are slave timer instances that are associated with a master instance linked to this timer: namely, those slave instances still point to the freed timer object although the master instance is unlinked, which may lead to user-after-free. The bug can be easily triggered particularly when a new userspace-driven timers (CONFIG_SND_UTIMER) is involved, since it can create and delete the timer object via a simple file open/close, while the other applications may keep accessing to that timer. This patch is an attempt to paper over the problem above: now instead of just unlinking, call snd_timer_close[_locked]() forcibly for each pending timer instance, so that all assigned slave timer instances are properly detached, too. Since snd_timer_close() might be called later by the driver that created that instance, the check of SNDRV_TIMER_IFLG_DEAD is added at the beginning, too. A flaw was found in the Linux kernel's Advanced Linux Sound Architecture (ALSA) timer component.
High [CVE-2026-53235] add pskb_may_pull to skb_gro_receive_list
In the Linux kernel, the following vulnerability has been resolved: net: add pskb_may_pull() to skb_gro_receive_list() skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without first ensuring the data is in the linear area via pskb_may_pull(). When the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in page fragments) while skb_gro_offset is non-zero (after IP+TCP header parsing). The skb_pull() then decrements skb->len by skb_gro_offset but skb->data_len stays unchanged, hitting BUG_ON(skb->len data_len) in __skb_pull(). The UDP fraglist GRO path already contains this guard at udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides centralized protection for all callers (TCP, UDP, and any future protocols), and ensures the precondition of skb_pull() is satisfied before it is called. On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the skb is not held as a new GRO head and is instead delivered through the normal receive path, matching the UDP handling. A flaw was found in the Linux kernel's network Generic Receive Offload (GRO) handling. An attacker sending specially crafted network packets could trigger a bug in the `skb_gro_receive_list()` function. This occurs when the system attempts to process network data that is not in the expected linear memory area, leading to an incorrect buffer length calculation.
High [CVE-2026-53131] require Ethernet MAC header before using eth_hdr
In the Linux kernel, the following vulnerability has been resolved: netfilter: require Ethernet MAC header before using eth_hdr() `ip6t_eui64`, `xt_mac`, the `bitmap:ip,mac`, `hash:ip,mac`, and `hash:mac` ipset types, and `nf_log_syslog` access `eth_hdr(skb)` after either assuming that the skb is associated with an Ethernet device or checking only that the `ETH_HLEN` bytes at `skb_mac_header(skb)` lie between `skb->head` and `skb->data`. Make these paths first verify that the skb is associated with an Ethernet device, that the MAC header was set, and that it spans at least a full Ethernet header before accessing `eth_hdr(skb)`. Certain netfilter modules, including `ip6t_eui64` and `xt_mac`, accessed Ethernet MAC header data without first verifying that an Ethernet device was associated with the network packet or that the MAC header was present and of sufficient length. This oversight could allow a local or remote attacker to trigger an out-of-bounds read, potentially 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). Weakness: CWE-125. 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. Will not fix / out of support: Red Hat Enterprise Linux 6.
High [CVE-2026-53209] reject oversized Broadcast Announcement prepend
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: reject oversized Broadcast Announcement prepend Existing advertising instances can already hold the maximum extended advertising payload. When hci_adv_bcast_annoucement() prepends the Broadcast Announcement service data to that payload, the combined data may no longer fit in the temporary buffer used to rebuild the advertising data. Reject that case before copying the existing payload and report the failure through the device log. This keeps the existing advertising data intact and avoids overrunning the temporary buffer. A flaw was found in the Bluetooth subsystem of the Linux kernel, specifically within the `hci_sync` component. This vulnerability occurs when the `hci_adv_bcast_annoucement()` function attempts to prepend Broadcast Announcement service data to an existing advertising payload that is already at its maximum size. This can lead to an oversized data packet that may overrun a temporary buffer, potentially causing a denial of service (DoS) or other unpredictable system behavior. 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-131. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53208] reject BR/EDR signaling packets over MTUsig
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: reject BR/EDR signaling packets over MTUsig net/bluetooth/l2cap_core.c:l2cap_sig_channel() accepts BR/EDR signaling packets up to the channel MTU and dispatches each command without enforcing the signaling MTU (MTUsig). A Bluetooth BR/EDR peer within radio range can send a fixed-channel CID 0x0001 packet that is larger than MTUsig and contains many L2CAP_ECHO_REQ commands before pairing. In a real-radio stock-kernel run, one 681-byte signaling packet containing 168 zero-length ECHO_REQ commands made the target transmit 168 ECHO_RSP frames over about 220 ms. Define Linux's BR/EDR signaling MTU as the spec minimum of 48 bytes and reject any larger signaling packet with one L2CAP_COMMAND_REJECT_RSP carrying L2CAP_REJ_MTU_EXCEEDED before any command is dispatched. The Bluetooth Core spec wording for MTUExceeded says the reject identifier shall match the first request command in the packet, and that packets containing only responses shall be silently discarded. Linux intentionally deviates from that prescription: silently discarding desynchronizes the peer because the remote stack never learns its responses were dropped, and locating the first request command requires walking command headers past MTUsig, i.e. processing bytes from a packet we have already decided is too large to process.
High [CVE-2026-53224] validate embedded INIT chunk and address list lengths in cookie
In the Linux kernel, the following vulnerability has been resolved: sctp: validate embedded INIT chunk and address list lengths in cookie sctp_unpack_cookie() only checked that the embedded INIT chunk length did not exceed the remaining cookie payload, but did not ensure that the INIT chunk is large enough to contain a complete INIT header. A malformed COOKIE_ECHO can therefore carry a truncated INIT chunk whose length field is smaller than sizeof(struct sctp_init_chunk). Later, sctp_process_init() accesses INIT parameters unconditionally, which may lead to out-of-bounds reads. In addition, raw_addr_list_len is not fully validated against the remaining cookie payload. When cookie authentication is disabled, an attacker can supply an oversized raw_addr_list_len and cause sctp_raw_to_bind_addrs() to read beyond the end of the cookie. The address parser also lacks sufficient bounds checks for parameter headers and lengths, allowing malformed address parameters to trigger out-of-bounds reads. Fix this by: - requiring the embedded INIT chunk length to be at least sizeof(struct sctp_init_chunk); - validating that the INIT chunk and raw address list together fit within the cookie payload; - verifying sufficient data exists for each address parameter header and payload before parsing it.
High [CVE-2026-53268] fix possible out-of-bounds read
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack_irc: fix possible out-of-bounds read When parsing fails after we've matched the command string we should bail out instead of trying to match a different command. This helper should be deprecated, given prevalence of TLS I doubt it has any relevance in 2026. When parsing network traffic, if a command string is matched but subsequent parsing fails, the system does not properly exit, leading to the flaw. This could potentially allow an attacker to cause a denial of service or disclose sensitive information. 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 6; 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 6. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53246] validate cached peer INIT chunk length in COOKIE_ECHO processing
In the Linux kernel, the following vulnerability has been resolved: sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing When a listening SCTP server processes a COOKIE_ECHO chunk, the cached peer INIT chunk embedded after the cookie is parsed and its parameters are later walked by sctp_process_init() using sctp_walk_params(). However, the chunk header length of this cached INIT chunk was not validated against the remaining buffer in the COOKIE_ECHO payload. If the length field is inflated, the parameter walk can run beyond the actual received data, leading to out-of-bounds reads and potential memory corruption during later parameter handling (e.g. STATE_COOKIE processing and kmemdup() copies). Add a bounds check in sctp_unpack_cookie() to ensure the cached INIT chunk length does not exceed the available data in the COOKIE_ECHO buffer before it is used. A flaw was found in the Linux kernel's Stream Control Transmission Protocol (SCTP) implementation. A remote attacker could exploit this by sending a specially crafted COOKIE_ECHO chunk to a listening SCTP server. The server's failure to properly validate the length of a cached peer INIT chunk within the COOKIE_ECHO payload could lead to out-of-bounds reads and memory corruption. This could result in a denial of service or potentially information disclosure.
High [CVE-2026-53239] fix use-after-free on inexact bin in xfrm_policy_bysel_ctx
In the Linux kernel, the following vulnerability has been resolved: xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx() Fix the race by pruning the bin while still holding xfrm_policy_lock, before dropping it. Use __xfrm_policy_inexact_prune_bin() directly since the lock is already held. The wrapper xfrm_policy_inexact_prune_bin() becomes unused and is removed. Race: CPU0 (XFRM_MSG_DELPOLICY) CPU1 (XFRM_MSG_NEWSPDINFO) ========================== ========================== xfrm_policy_bysel_ctx(): spin_lock_bh(xfrm_policy_lock) bin = xfrm_policy_inexact_lookup() __xfrm_policy_unlink(pol) spin_unlock_bh(xfrm_policy_lock) xfrm_policy_kill(ret) // wide window, lock not held xfrm_hash_rebuild(): spin_lock_bh(xfrm_policy_lock) __xfrm_policy_inexact_flush(): kfree_rcu(bin) // bin freed spin_unlock_bh(xfrm_policy_lock) xfrm_policy_inexact_prune_bin(bin) // UAF: bin is freed A race condition exists in the `xfrm` policy handling, specifically within the `xfrm_policy_bysel_ctx()` function. This flaw allows for a use-after-free vulnerability, where memory is accessed after it has been released. This can lead to system instability or a denial of service (DoS), making the system unresponsive or causing it to crash. 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-364.
High [CVE-2026-53167] limit FUSE_NOTIFY_RETRIEVE to uptodate folios
In the Linux kernel, the following vulnerability has been resolved: fuse: limit FUSE_NOTIFY_RETRIEVE to uptodate folios FUSE_NOTIFY_RETRIEVE must be limited to uptodate folios;!uptodate folios can contain uninitialized data. Since FUSE_NOTIFY_RETRIEVE is intended to only return data that is already in the page cache and not wait for data from the FUSE daemon, treat!uptodate folios as if they weren't present. This only has security impact on systems that don't enable automatic zero-initialization of all page allocations via CONFIG_INIT_ON_ALLOC_DEFAULT_ON or init_on_alloc=1. A flaw was found in the Linux kernel's FUSE (Filesystem in Userspace) component. The FUSE_NOTIFY_RETRIEVE operation did not properly restrict access to up-to-date folios, potentially allowing the exposure of uninitialized data from the page cache. This information disclosure vulnerability could allow an attacker to access sensitive information. 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-908. 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. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE.
High [CVE-2026-53262] hold reference to session in pppol2tp_ioctl
In the Linux kernel, the following vulnerability has been resolved: l2tp: pppol2tp: hold reference to session in pppol2tp_ioctl() pppol2tp_ioctl() read sock->sk->sk_user_data directly without any locks or reference counting. If a controllable sleep was induced during copy_from_user() (e.g. via a userfaultfd page fault sleep), a concurrent socket close could trigger pppol2tp_session_close() asynchronously. This frees the l2tp_session structure via the l2tp_session_del_work workqueue. Upon resuming, the ioctl thread dereferences the stale session pointer, resulting in a Use-After-Free (UAF). Fix this by securely fetching the session reference using the RCU-safe, refcounted helper pppol2tp_sock_to_session(sk) on entry. This locks the session's refcount across the sleep. We structured the function to exit via standard err breaks, guaranteeing that l2tp_session_put() is cleanly called on all return paths to drop the reference. To preserve existing behavior we validate the session and its magic signature only for the specific L2TP commands that require it. This ensures that generic/unknown ioctls called on an unconnected socket still return -ENOIOCTLCMD and correctly fall back to generic handlers (e.g. in sock_do_ioctl()). This Use-After-Free (UAF) vulnerability arises from improper handling of session references within the `pppol2tp_ioctl()` function.