Red Hat Security Advisory: kernel security, bug fix, and enhancement update

Fixed packages 52

Vulnerabilities 5

• High 7.8
  CVE-2025-39964 Exploited Public exploit

  crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg

  In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion. Furthermore, c…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Oct 13, 2025

  KEV Sep 18, 2026
• Critical 9.8
  CVE-2026-74581

  net: ipv6: clear suppressed fib6 rule result

  In the Linux kernel, the following vulnerability has been resolved: net: ipv6: clear suppressed fib6 rule result fib6_rule_suppress() drops a suppressed route with ip6_rt_put_flags(), but leaves res->rt6 pointing at the released rt6_info. If no later rule sup…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Aug 21, 2026
• High 8.8
  CVE-2026-74469 Public exploit

  sctp: prevent peer transport count overflow

  In the Linux kernel, the following vulnerability has been resolved: sctp: prevent peer transport count overflow sctp_assoc_add_peer() increments the association's 16-bit transport_count for every new unique peer. Adding the 65,536th transport wraps the count …

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Aug 15, 2026
• High 7.8
  CVE-2026-68121 Public exploit

  pppoe: reload header pointer after dev_hard_header()

  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 th…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  Aug 10, 2026
• High 7.8
  CVE-2026-81000 Public exploit

  net: tun: bound receive headroom

  In the Linux kernel, the following vulnerability has been resolved: net: tun: bound receive headroom tun_get_user() uses tun->align both as skb headroom and when choosing how much packet data to keep linear. OVS can propagate an oversized headroom request fro…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Sep 11, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2403545
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2513233
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2517043
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2520980
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2532176
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_73788.json
• report
  https://access.redhat.com/security/cve/CVE-2025-39964
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-39964
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-39964
• article
  https://lore.kernel.org/linux-cve-announce/2025101334-CVE-2025-39964-7964@gregkh/T
• article
  https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• report
  https://access.redhat.com/security/cve/CVE-2026-68121
• article
  https://access.redhat.com/security/vulnerabilities/RHSB-2026-011
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-68121
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-68121
• article
  https://lore.kernel.org/linux-cve-announce/2026081056-CVE-2026-68121-b20f@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-74469
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-74469
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-74469
• article
  https://lore.kernel.org/linux-cve-announce/2026081534-CVE-2026-74469-d3f3@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-74581
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-74581
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-74581
• article
  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6aea62e433fe1b586202a5fee8b5807ce635e1d7
• report
  https://access.redhat.com/security/cve/CVE-2026-81000
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-81000
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-81000
• article
  https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-81000.mbox