Red Hat Linux RHEL & SELinux Vulnerabilities & Security Advisories
1658 advisories tracked · Red Hat Security Data API · 2 listed in the CISA Known Exploited Vulnerabilities catalog
Every row below is a published Red Hat Linux advisory that VulniPulse classified as RHEL & SELinux, with the CVEs, affected and fixed releases and exploitation status the vendor stated. Severity mix: 33 critical, 634 high, 818 medium, 171 low.
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Latest Red Hat RHEL & SELinux advisories
Medium [CVE-2026-14899] Off-by-one out of bounds read in MIME header parser for forwarding
The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13. Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory. Red Hat severity: Moderate — CVSS 6.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N). Weakness: CWE-125. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 10.0 Extended Update Support; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support; Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On; Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support; Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On; Red Hat Enterprise Linux 8.8 Telecommunications Update Service; Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions; Red Hat Enterprise Linux 9; Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions; Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions; Red Hat Enterprise Linux 9.6 Extended Update Support; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7.
Medium [CVE-2026-16615] weak random number generation in pkce implementation
A flaw was found in librest. The PKCE implementation for OAuth authorization uses the GRand function from the GLib API, a cryptographically insecure pseudo-random number generator. Because the generated "code verifier" lacks sufficient cryptographic entropy, a malicious actor can reverse-engineer the pseudo-random number generator (PRNG) seed to predict or reconstruct the code verifier string, allowing an attacker to bypass PKCE protections and successfully impersonate the client during the OAuth 2.0 authorization flow. This allows the attacker to hold a valid access token and impersonate the user, access their protected data and perform actions on their behalf. Due to these reasons, this vulnerability has been rated with an important severity. Red Hat severity: Important — CVSS 6.8 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N). Weakness: CWE-338. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 10.0 Extended Update Support. Red Hat fixing advisory: RHSA-2026:47085, RHSA-2026:62222. Affected products named by the advisory: Red Hat package: rest.
Medium [CVE-2026-53910] heap‑based buffer overflow due to multiple signed integer overflows in line‑mapping calculations
diff3 tool from GNU diffutils is vulnerable to a heap‑based buffer overflow due to multiple signed integer overflows in line‑mapping calculations. Incorrect arithmetic in mapping line ranges can result in corrupted values being used for memory allocation and loop bounds. When processing crafted diff output, these overflows may cause the application to allocate insufficient memory and subsequently perform out‑of‑bounds writes during internal processing. An attacker who can control the output of the diff program used by diff3 (e.g. via --diff-program pointing to a malicious script) can trigger out-of-bounds writes, resulting in a crash and potentially remote code execution depending on the environment. This issue has been fixed in commit 9ff04d5b84743e331e80b589335a52c5480d1815 NOTE: The project maintainers claim that this is not a security issue. They state that the worst outcome this issue can cause is a crash of diff and that it cannot be used to escalate privileges. A flaw was found in the diff3 program in the diffutils package. An attacker often needs prior execution privileges to supply the malicious diff output, meaning they already have the ability to execute arbitrary scripts on the system. Due to these reasons, this vulnerability has been rated with a low severity. Red Hat severity: Low — CVSS 5.3 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L). Weakness: CWE-190.
Medium [CVE-2026-56416] Heap buffer overflow via malformed DNSSEC record
In NLnet Labs Unbound up to and including version 1.25.1, when the validator builds the canonical RDATA form for an RRSIG-covered PX/RP/MINFO/SOA RRset, it computes the address of the second embedded domain name as 'datstart + dname_valid(datstart,...)' and passes it straight to 'query_dname_tolower()' without checking that a second name is actually present in the RDATA. The wire-format parser accepts multi-dname RRs whose RDATA ends after the first name, so an attacker who runs a DNSSEC-signed authoritative server can deliver a record with an absent second domain name (e.g. SOA record) and cause 'query_dname_tolower()' to walk label-by-label through stale bytes in the per-worker 'env->scratch_buffer', past the end of that heap allocation if 'msg-buffer-size' has been lowered from the default. This leads to heap buffer overflow and on a release build the outcome relies heavily on the contents of the buffer tail and the adjacent heap chunk. A vulnerability in Unbound allows remote attackers using malicious DNSSEC-signed servers to send malformed records that trigger a heap buffer overflow. This can cause a denial of service or potential limited information disclosure. Exploitation requires the Unbound DNSSEC validator to process malformed records, which may be exacerbated if `msg-buffer-size` is configured below its default value.
Medium [CVE-2026-55991] Denial of Service via crafted DNS-over-QUIC connection
In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a remote unauthenticated client can trigger a libngtcp2 assertion (if compiled with assertions on) and terminate the entire Unbound process using a single DNS-over-QUIC (DoQ) connection and one normal DNS query. This is caused by an erroneous error value passed to libngtcp2. When 'ngtcp2_conn_writev_stream()' returns 'NGTCP2_ERR_STREAM_DATA_BLOCKED', Unbound continues to call 'ngtcp2_ccerr_set_application_error()' with a '-1' error value. The 'int' literal '-1' is implicitly converted to the function's 'uint64_t error_code' parameter as '0xFFFFFFFFFFFFFFFF'. The follow-on 'ngtcp2_conn_write_connection_close()' serialises that value as a QUIC variable-length integer; because '2^64-1' exceeds the 62-bit varint ceiling, 'ngtcp2_put_uvarintlen()' fails 'assert(n < 4611686018427387904ULL)' and the whole resolver process aborts. A remote, unauthenticated DoQ client can trigger this deterministically with a single QUIC connection by advertising 'initial_max_stream_data_bidi_local = 1' in its transport parameters and sending one DoQ query without ever reading the stream. A flaw was found in Unbound. This results in a Denial of Service (DoS), making the DNS resolver unavailable. This Moderate flaw in Unbound allows a remote, unauthenticated client to cause a denial of service.
Medium [CVE-2026-55990] Denial of Service via faulty DNSCrypt configuration
In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, when the 'dnscrypt:' clause lists more 'dnscrypt-provider-cert:' files than there are matching 'dnscrypt-secret-key:' files, Unbound fills only the matched prefix and leaves the tail slots at the '0xdb' fill that libsodium's allocator writes into every allocation. Unbound would then iterate over the number of cert files, not the actual slots, so it walks into a slot with garbage data filled with '0xdb' bytes. Any unauthenticated client that sends one UDP datagram of ≥ 68 bytes whose first 8 bytes are '0xdb' to 'dnscrypt-port' will use that garbage entry which leads to a garbage dereference killing the server. This is a silent faulty configuration that goes unnoticed until triggered with the right client query. Unbound needs to be compiled with DNSCrypt support ('--enable-dnscrypt'). An unauthenticated remote attacker could exploit a faulty configuration, where an imbalance between DNSCrypt provider certificate and secret key files leads to memory corruption. By sending a specially crafted network request, the attacker can cause a garbage dereference, leading to a server crash and a denial of service (DoS). This Moderate flaw in Unbound can lead to a denial of service if the DNSCrypt feature is enabled and misconfigured. An unauthenticated attacker could then send a crafted UDP packet to trigger a server crash.
Medium [CVE-2026-50251] Denial of Service via crafted DNS glue records
In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled (set to any value greater than zero), glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies since the remote IP does not match the original source IP of 0.0.0.0/::0. This behavior keeps on looping for the glue records and pushing the counter to the configured 'unwanted-reply-threshold' that triggers a defensive cache clear. A malicious actor who controls a delegation that returns in-bailiwick glue of 0.0.0.0/::0 can drive the counter to the limit of 'unwanted-reply-threshold' to the threshold and trigger a cache clean of the message and rrset caches; at will, indefinitely, without sending a single spoofed packet. The iterator uses the 0.0.0.0/::0 glue, and a system that can route this (e.g., Linux kernel routes the datagram over loopback), Unbound's own listener answers from 127.0.0.1. Because of the mismatch of 0.0.0.0 and 127.0.0.1, in this example, Unbound accounts the reply as an unwanted (probably spoofed) answer. The counter resets to zero on every cache flush, so the attack loops forever. A flaw was found in Unbound. A remote malicious actor can exploit a vulnerability by controlling a DNS delegation that returns specific glue records.
Medium [CVE-2026-14586] Denial of Service via assertion failure in DNS-over-QUIC environments
In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, in DNS-over-QUIC environments, with high concurrency and under pressure, an assertion in libngtcp2 about monotonic timestamps could trigger and result in server termination and thus denial of service. When interfacing with libngtcp2, for DNS-over-QUIC support in Unbound, it is expected to use monotonic time. Unbound was using realtime instead, and in DoQ environments with high concurrency and under pressure, an assert in libngtcp2 for the quic timestamp would trigger and terminate the server. This vulnerability needs Unbound to be compiled with DoQ support ('--with-libngtcp2') and the 'quic-port' to be configured for the listening interfaces. Under heavy DNS-over-QUIC (DoQ) traffic, a timing discrepancy in Unbound’s libngtcp2 library can trigger an assertion failure. This causes the server to crash unexpectedly, resulting in a denial of service (DoS). Moderate: This Unbound vulnerability, leading to a denial of service, is contingent on the resolver being compiled with DNS-over-QUIC (DoQ) support and having a `quic-port` configured. The flaw manifests under high concurrency and network pressure due to a timing discrepancy in the `libngtcp2` library. Red Hat deployments not utilizing DoQ or without the `quic-port` enabled are not affected.
Medium [CVE-2026-16560] heap-buffer-overflow in rdn_av_swap on quoted multivalued RDN
A heap-buffer-overflow flaw was found in Directory Server (389-ds-base). When a DN contains a legacy-quoted value, the server won't close the heap allocation allowing another call to refer to the same memory pointer causing a denial of service or an arbitrary memory write operation. Red-hat rates this vulnerability as Moderate impact. The function can allow an unauthenticated attacker to send malformed DN requests and trigger the bug. Denial of service is more reliably observed when heap debugging is enabled (for example AddressSanitizer or MALLOC_CHECK_=3), or depending on heap layout and subsequent memory allocator activity. There is no configuration switch to disable DN normalization for client-supplied DNs. Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). Weakness: CWE-1220. Affected Red Hat products: Red Hat Directory Server 11; Red Hat Directory Server 12; Red Hat Directory Server 13; 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: 389-ds-base.
Medium [CVE-2026-16473] heap out-of-bounds read via crafted sbc audio frame
A flaw was found in the sbc library (BlueZ SBC codec). An off-by-one error in the SBC frame decoder allows a crafted audio payload to trigger a one-byte heap out-of-bounds read. This could allow an adjacent attacker streaming Bluetooth audio to read a single byte of adjacent heap memory. Red Hat severity: Moderate — CVSS 4.3 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N). 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 does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: sbc.
Medium [CVE-2026-10723] Incorrect acceptance of NSEC3 records
BIND may accept incorrect child-zone NSEC3 records as valid, which could allow an attacker to forge authenticated NXDOMAIN responses. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. Exploitation requires high attack complexity, limiting the immediate risk to Red Hat products. Red Hat severity: Moderate — CVSS 6.8 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N). Weakness: CWE-345. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 7 Extended Lifecycle Support; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions; Red Hat Enterprise Linux 9.6 Extended Update Support; Red Hat OpenShift Container Platform 4.16; Red Hat OpenShift Container Platform 4.18; Red Hat OpenShift Container Platform 4.22; Red Hat Hardened Images; Red Hat Enterprise Linux 6; Red Hat OpenShift Container Platform 4. Red Hat lists Red Hat Enterprise Linux 9 as not affected. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat fixing advisory: RHSA-2026:55437, RHSA-2026:60383, RHSA-2026:54509, RHSA-2026:54654, RHSA-2026:54510, RHSA-2026:55442, RHSA-2026:57189, RHSA-2026:55441, RHSA-2026:62549, RHSA-2026:65851, RHSA-2026:60440, RHSA-2026:54071.
Medium [CVE-2026-10822] Key Record using PRIVATEDNS algorithm may lead to exit
If BIND encounters a particular invalid data structure in a DNS record, it will accept the invalid data, and may subsequently abort and exit. BIND will first need to store a DNS record for a key (KEY, DNSKEY, etc.). That key must specify a PRIVATEDNS algorithm (253), and in the algorithm identifier, improperly give a length longer than the actual identifier data. If BIND later needs to render that record to text, it will use the invalid length during processing, leading to a consistency check failing. This Moderate impact flaw in BIND allows a specially crafted DNS key record with a PRIVATEDNS algorithm and overlong algorithm identifier to cause the named daemon to abort when rendering the record to text. The attack requires prior storage of the malformed record (requiring user interaction), limiting the immediate risk to most Red Hat deployments. Red Hat severity: Moderate — CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H). Weakness: CWE-617. Affected Red Hat products: Red Hat Hardened Images; 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. Red Hat fixing advisory: RHSA-2026:54071. Affected products named by the advisory: Red Hat package: bind9.16; Red Hat package: bind9.18; Red Hat package: dhcp.
Medium [CVE-2026-46917] Improve DTLS handshaking (Oracle CPU 2026-07)
Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: JSSE). Note: This vulnerability can only be exploited by supplying data to APIs in the specified Component without using Untrusted Java Web Start applications or Untrusted Java applets, such as through a web service. CVSS 3.1 Base Score 5.3 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). A flaw was found in OpenJDK. The DTLS implementation is open to two different DoS attacks. Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). Weakness: CWE-400. Affected products named by the advisory: OPENJDK ELS 11.0.32; Red Hat Build of OpenJDK 17.0.20; Red Hat Build of OpenJDK 21.0.12; Red Hat Build of OpenJDK 25.0.4; and 20 more.
Medium [CVE-2026-47021] Enhance XBM image support (Oracle CPU 2026-07)
Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: 2D). Note: This vulnerability can be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs. This vulnerability also applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. CVSS 3.1 Base Score 5.3 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). A flaw was found in OpenJDK. The regex defined in XbmImageDecoder (matchRegex) is vulnerable to a DoS attack when the input contains a long string without a closing character; due to excessive backtracking. Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). Weakness: CWE-1333. Affected products named by the advisory: OPENJDK ELS 11.0.32; Red Hat Build of OpenJDK 17.0.20; Red Hat Build of OpenJDK 21.0.12; Red Hat Build of OpenJDK 25.0.4; and 21 more.
Medium [CVE-2026-47027] Enhance Jar file processing (Oracle CPU 2026-07)
Vulnerability in Oracle Java SE (component: Libraries). Supported versions that are affected are Oracle Java SE: 8u491, 8u491-perf, 11.0.31, 17.0.19, 21.0.11, 25.0.3, 26.0.1; Oracle GraalVM for JDK: 17.0.19 and 21.0.11; Oracle GraalVM Enterprise Edition: 21.3.18. Easily exploitable vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE. Successful attacks of this vulnerability can result in unauthorized ability to cause a partial denial of service (partial DOS) of Oracle Java SE. Note: This vulnerability can be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs. This vulnerability also applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. CVSS 3.1 Base Score 5.3 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). A flaw was found in OpenJDK. The processImpl() method in SignatureFileVerifier exhibits O(n^2) time complexity when verifying JAR files where different entries have different signer combinations, potentially leading to DoS. Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).
Medium [CVE-2026-60147] Improve certification checking (Oracle CPU 2026-07)
Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: Security). Note: This vulnerability can be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs. This vulnerability also applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. CVSS 3.1 Base Score 6.5 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N). A flaw was found in OpenJDK. OpenJDK can apply two different security meanings to the same wildcard dNSName SAN across certificate policy enforcement and hostname verification. During path validation, DNSName.constrains compares *.foo.com and secret.foo.com literally and returns NAME_SAME_TYPE, so NameConstraintsExtension.verify does not reject the chain when secret.foo.com is an exact-host exclusion. Later, HostnameChecker interprets the same SAN as a wildcard template and accepts secret.foo.com for *.foo.com. Red Hat severity: Moderate — CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N). Weakness: CWE-295.
Medium [CVE-2026-12548] heap out-of-bounds read in libsoup due to integer truncation
A heap out-of-bounds read flaw was found in libsoup. When parsing multipart HTTP messages, an integer type mismatch between the caller and soup_headers_parse() can cause the length parameter to be incorrectly truncated, leading to a heap buffer over-read. A remote attacker could use this flaw to crash an application using libsoup or potentially disclose heap memory contents. Red Hat severity: Moderate — CVSS 4.2 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L). Weakness: CWE-125. Affected Red Hat products: Red Hat Enterprise Linux 10. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: libsoup3.
Medium [CVE-2026-59850] use-after-free via data callbacks on closed channels
A flaw was found in libssh. If data packets are processed after a channel is closed, channel data callbacks can be invoked after the associated data has already been freed, leading to crashes or possible use-after-free conditions. Red Hat severity: Moderate — CVSS 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L). Weakness: CWE-416. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Hardened Images. Red Hat fixing advisory: RHSA-2026:55855, RHSA-2026:62218, RHSA-2026:62217, RHSA-2026:42922. Affected products named by the advisory: Red Hat package: libssh.
Medium [CVE-2026-59848] denial of service via SFTP responses with unknown request IDs
A flaw was found in libssh. A malicious SFTP server can send responses for unknown request IDs that libssh clients keep queued indefinitely, causing unbounded memory growth and client-side denial of service. Red Hat severity: Moderate — CVSS 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). Weakness: CWE-770. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Hardened Images. Red Hat fixing advisory: RHSA-2026:55855, RHSA-2026:62218, RHSA-2026:62217, RHSA-2026:42922. Affected products named by the advisory: Red Hat package: libssh.
Medium [CVE-2026-59847] integrity downgrade via OpenSSL AES-GCM tag verification
A flaw was found in libssh. Incorrect AES-GCM finalization checks in builds using the OpenSSL backend can effectively remove integrity protection, allowing an in-path attacker to modify plaintext on the wire without detection. Red Hat severity: Moderate — CVSS 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N). Weakness: CWE-253. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Hardened Images. Red Hat fixing advisory: RHSA-2026:55855, RHSA-2026:62218, RHSA-2026:62217, RHSA-2026:42922. Affected products named by the advisory: Red Hat package: libssh.