ESB-2026.4819

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.4819 kernel security update 8 May 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: kernel Publisher: Red Hat Operating System: Red Hat Resolution: Patch/Upgrade CVE Names: CVE-2026-31402 CVE-2026-23191 CVE-2025-40240 CVE-2018-16885 Original Bulletin: https://access.redhat.com/errata/RHSA-2026:14925 Comment: CVSS (Max): 7.8 CVE-2026-31402 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) CVSS Source: Red Hat Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H EPSS (Max): 0.2% (37th) CVE-2026-31402 2026-05-07 - --------------------------BEGIN INCLUDED TEXT-------------------- RHSA-2026:14925 - Security Advisory Issued: 2026-05-07 Updated: 2026-05-07 Synopsis Kernel security update Type/Severity Security Advisory: Important Topic An update for kernel is now available for Red Hat Enterprise Linux 7 Extended Lifecycle Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. Description The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): o kernel: out-of-bound read in memcpy_fromiovecend() (CVE-2018-16885) o kernel: sctp: avoid NULL dereference when chunk data buffer is missing (CVE-2025-40240) o kernel: ALSA: aloop: Fix racy access at PCM trigger (CVE-2026-23191) o kernel: nfsd: fix heap overflow in NFSv4.0 LOCK replay cache (CVE-2026-31402) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Solution For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Affected Products o Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64 o Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x o Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64 o Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le Fixes o BZ - 1661503 - CVE-2018-16885 kernel: out-of-bound read in memcpy_fromiovecend() o BZ - 2418832 - CVE-2025-40240 kernel: sctp: avoid NULL dereference when chunk data buffer is missing o BZ - 2439947 - CVE-2026-23191 kernel: ALSA: aloop: Fix racy access at PCM trigger o BZ - 2454844 - CVE-2026-31402 kernel: nfsd: fix heap overflow in NFSv4.0 LOCK replay cache CVEs o CVE-2018-16885 o CVE-2025-40240 o CVE-2026-23191 o CVE-2026-31402 References o https://access.redhat.com/security/updates/classification/#important - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. 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