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Fencer Intel
high 7.8

CVE-2025-39955 json

tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect().

published last yr. modified 21d ago also EUVD-2025-33328

cvss
7.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect().

syzbot reported the splat below where a socket had tcp_sk(sk)->fastopen_rsk in the TCP_ESTABLISHED state. [0]

syzbot reused the server-side TCP Fast Open socket as a new client before the TFO socket completes 3WHS:

1. accept() 2. connect(AF_UNSPEC) 3. connect() to another destination

As of accept(), sk->sk_state is TCP_SYN_RECV, and tcp_disconnect() changes it to TCP_CLOSE and makes connect() possible, which restarts timers.

Since tcp_disconnect() forgot to clear tcp_sk(sk)->fastopen_rsk, the retransmit timer triggered the warning and the intended packet was not retransmitted.

Let's call reqsk_fastopen_remove() in tcp_disconnect().

[0]: WARNING: CPU: 2 PID: 0 at net/ipv4/tcp_timer.c:542 tcp_retransmit_timer (net/ipv4/tcp_timer.c:542 (discriminator 7)) Modules linked in: CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted 6.17.0-rc5-g201825fb4278 #62 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:tcp_retransmit_timer (net/ipv4/tcp_timer.c:542 (discriminator 7)) Code: 41 55 41 54 55 53 48 8b af b8 08 00 00 48 89 fb 48 85 ed 0f 84 55 01 00 00 0f b6 47 12 3c 03 74 0c 0f b6 47 12 3c 04 74 04 90 <0f> 0b 90 48 8b 85 c0 00 00 00 48 89 ef 48 8b 40 30 e8 6a 4f 06 3e RSP: 0018:ffffc900002f8d40 EFLAGS: 00010293 RAX: 0000000000000002 RBX: ffff888106911400 RCX: 0000000000000017 RDX: 0000000002517619 RSI: ffffffff83764080 RDI: ffff888106911400 RBP: ffff888106d5c000 R08: 0000000000000001 R09: ffffc900002f8de8 R10: 00000000000000c2 R11: ffffc900002f8ff8 R12: ffff888106911540 R13: ffff888106911480 R14: ffff888106911840 R15: ffffc900002f8de0 FS: 0000000000000000(0000) GS:ffff88907b768000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8044d69d90 CR3: 0000000002c30003 CR4: 0000000000370ef0 Call Trace: <IRQ> tcp_write_timer (net/ipv4/tcp_timer.c:738) call_timer_fn (kernel/time/timer.c:1747) __run_timers (kernel/time/timer.c:1799 kernel/time/timer.c:2372) timer_expire_remote (kernel/time/timer.c:2385 kernel/time/timer.c:2376 kernel/time/timer.c:2135) tmigr_handle_remote_up (kernel/time/timer_migration.c:944 kernel/time/timer_migration.c:1035) __walk_groups.isra.0 (kernel/time/timer_migration.c:533 (discriminator 1)) tmigr_handle_remote (kernel/time/timer_migration.c:1096) handle_softirqs (./arch/x86/include/asm/jump_label.h:36 ./include/trace/events/irq.h:142 kernel/softirq.c:580) irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680 kernel/softirq.c:696) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 (discriminator 35) arch/x86/kernel/apic/apic.c:1050 (discriminator 35)) </IRQ>

Patch / fix

  • Linux Linux 5.4.300, 5.10.245, 5.15.194, 6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17
  • linux Debian 12 6.1.158-1
  • linux Debian 13 6.12.57-1
  • linux Debian 14 6.16.9-1

debian advisories DEBIAN-CVE-2025-39955

  • linux Ubuntu 22.04 LTS 5.15.0-170.180
  • linux Ubuntu 24.04 LTS 6.8.0-106.106
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1100.107
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1050.53
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1100.109
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1052.55
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1096.102
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1048.53

ubuntu advisories UBUNTU-CVE-2025-39955

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel RHEL 9 5.14.0-611.11.1.el9_7
  • rv RHEL 9 5.14.0-611.11.1.el9_7
  • perf RHEL 9 5.14.0-611.11.1.el9_7
  • rtla RHEL 9 5.14.0-611.11.1.el9_7
  • libperf RHEL 9 5.14.0-611.11.1.el9_7
  • kernel-rt RHEL 9 5.14.0-611.11.1.el9_7
  • kernel-64k RHEL 9 5.14.0-611.11.1.el9_7
  • kernel-core RHEL 9 5.14.0-611.11.1.el9_7

red hat advisories RHSA-2025:23960RHSA-2025:23947RHSA-2025:23463RHSA-2025:23450RHSA-2025:23425RHSA-2025:23422

  • kernel-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.58.1
  • kernel-syms-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.58.1
  • kernel-rt_debug Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.58.1
  • kernel-source-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.58.1
  • kernel-rt Linux Micro 6.2 6.12.0-160000.7.1
  • kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.7.1
  • kernel-source SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.7.1
  • kernel-default SLES 16.0, SLE High Availability Extension 16.0, Linux Micro 6.2 +1 more 6.12.0-160000.7.1

suse advisories SUSE-SU-2025:4301-1SUSE-SU-2025:21080-1SUSE-SU-2025:21147-1SUSE-SU-2025:21180-1SUSE-SU-2026:20561-1SUSE-SU-2025:21052-1

  • kernel-rt openSUSE Leap 16.0 6.12.0-160000.7.1
  • dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.7.1
  • kernel-64kb openSUSE Leap 16.0 6.12.0-160000.7.1
  • kernel-syms openSUSE Leap 16.0 6.12.0-160000.7.1
  • kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.7.1
  • kernel-source openSUSE Leap 16.0 6.12.0-160000.7.1
  • kernel-default openSUSE Leap 16.0 6.12.0-160000.7.1
  • kernel-kvmsmall openSUSE Leap 16.0 6.12.0-160000.7.1

opensuse advisories openSUSE-SU-2025:20091-1

  • kernel-rt AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel-rt-core AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel-rt-modules AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel-rt-debug-core AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel-rt-debug-modules AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel-rt-modules-extra AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel-rt-debug-modules-extra AlmaLinux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel AlmaLinux 8 4.18.0-553.87.1.el8_10

almalinux advisories ALSA-2025:22387ALSA-2025:22388ALSA-2025:22405ALSA-2025:21931

  • kernel Rocky Linux 9 5.14.0-611.11.1.el9_7
  • kernel-rt Rocky Linux 8 4.18.0-553.87.1.rt7.428.el8_10
  • kernel Rocky Linux 8 4.18.0-553.87.1.el8_10
  • kernel Rocky Linux 10 6.12.0-124.13.1.el10_1

rocky linux advisories RLSA-2025:22405RLSA-2025:22387RLSA-2025:22388RLSA-2025:21931

  • kernel Azure Linux 3.0 6.6.112.1-1
  • kernel CBL-Mariner 2.0 5.15.200.1-1

azure linux advisories AZL-68328AZL-76431

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-39955 updated cvss 7.6

kernel: tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect()

  • Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-kvm, kernel-rt-core, kernel-rt-modules, kernel-rt-debug-kvm, kernel-rt-debug-core, +12 more
    affected: no fix available
  • Red Hat CodeReady Linux Builder EUS (v.9.4) libperf 5.14.0-427.103.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.103.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.103.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.103.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.103.1.el9_4
    fixed: vendor fix RHSA-2025:23450
  • Red Hat CodeReady Linux Builder EUS (v.9.6) libperf 5.14.0-570.69.1.el9_6, kernel-debuginfo-common-s390x 5.14.0-570.69.1.el9_6, kernel-debuginfo-common-x86_64 5.14.0-570.69.1.el9_6, kernel-debuginfo-common-aarch64 5.14.0-570.69.1.el9_6, kernel-debuginfo-common-ppc64le 5.14.0-570.69.1.el9_6
    fixed: vendor fix RHSA-2025:22392
  • Red Hat Enterprise Linux AppStream (v. 9) rv 5.14.0-611.11.1.el9_7, perf 5.14.0-611.11.1.el9_7, rtla 5.14.0-611.11.1.el9_7, python3-perf 5.14.0-611.11.1.el9_7, kernel-devel-matched 5.14.0-611.11.1.el9_7, kernel-64k-devel-matched 5.14.0-611.11.1.el9_7, +7 more
    fixed: vendor fix RHSA-2025:22405
  • Red Hat Enterprise Linux AppStream (v. 10) rv 6.12.0-124.13.1.el10_1, perf 6.12.0-124.13.1.el10_1, rtla 6.12.0-124.13.1.el10_1, python3-perf 6.12.0-124.13.1.el10_1, kernel-devel-matched 6.12.0-124.13.1.el10_1, kernel-64k-devel-matched 6.12.0-124.13.1.el10_1, +7 more
    fixed: vendor fix RHSA-2025:21931
  • Red Hat Enterprise Linux AppStream E4S (v.9.0) perf 5.14.0-70.158.1.el9_0, kernel-devel-matched 5.14.0-70.158.1.el9_0, kernel-debug-devel-matched 5.14.0-70.158.1.el9_0, kernel-debuginfo-common-s390x 5.14.0-70.158.1.el9_0, kernel-zfcpdump-devel-matched 5.14.0-70.158.1.el9_0, kernel-debuginfo-common-x86_64 5.14.0-70.158.1.el9_0, +2 more
    fixed: vendor fix RHSA-2025:23426
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) perf 5.14.0-284.150.1.el9_2, rtla 5.14.0-284.150.1.el9_2, kernel-devel-matched 5.14.0-284.150.1.el9_2, kernel-64k-devel-matched 5.14.0-284.150.1.el9_2, kernel-debug-devel-matched 5.14.0-284.150.1.el9_2, kernel-debuginfo-common-s390x 5.14.0-284.150.1.el9_2, +5 more
    fixed: vendor fix RHSA-2025:23423
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) rv 6.12.0-55.47.1.el10_0, perf 6.12.0-55.47.1.el10_0, rtla 6.12.0-55.47.1.el10_0, python3-perf 6.12.0-55.47.1.el10_0, kernel-devel-matched 6.12.0-55.47.1.el10_0, kernel-64k-devel-matched 6.12.0-55.47.1.el10_0, +7 more
    fixed: vendor fix RHSA-2025:22571
show 31 more
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) rv 5.14.0-427.103.1.el9_4, perf 5.14.0-427.103.1.el9_4, rtla 5.14.0-427.103.1.el9_4, kernel-devel-matched 5.14.0-427.103.1.el9_4, kernel-64k-devel-matched 5.14.0-427.103.1.el9_4, kernel-debug-devel-matched 5.14.0-427.103.1.el9_4, +6 more
    fixed: vendor fix RHSA-2025:23450
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) rv 5.14.0-570.69.1.el9_6, perf 5.14.0-570.69.1.el9_6, rtla 5.14.0-570.69.1.el9_6, python3-perf 5.14.0-570.69.1.el9_6, kernel-devel-matched 5.14.0-570.69.1.el9_6, kernel-64k-devel-matched 5.14.0-570.69.1.el9_6, +7 more
    fixed: vendor fix RHSA-2025:22392
  • Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-553.87.1.el8_10, kernel 4.18.0-553.87.1.el8_10, bpftool 4.18.0-553.87.1.el8_10, kernel-core 4.18.0-553.87.1.el8_10, kernel-tools 4.18.0-553.87.1.el8_10, python3-perf 4.18.0-553.87.1.el8_10, +15 more
    fixed: vendor fix RHSA-2025:22388
  • Red Hat Enterprise Linux BaseOS (v. 9) kernel 5.14.0-611.11.1.el9_7, kernel-64k 5.14.0-611.11.1.el9_7, kernel-core 5.14.0-611.11.1.el9_7, kernel-tools 5.14.0-611.11.1.el9_7, kernel-modules 5.14.0-611.11.1.el9_7, kernel-64k-core 5.14.0-611.11.1.el9_7, +27 more
    fixed: vendor fix RHSA-2025:22405
  • Red Hat Enterprise Linux BaseOS (v. 10) kernel 6.12.0-124.13.1.el10_1, kernel-64k 6.12.0-124.13.1.el10_1, kernel-core 6.12.0-124.13.1.el10_1, kernel-tools 6.12.0-124.13.1.el10_1, kernel-modules 6.12.0-124.13.1.el10_1, kernel-64k-core 6.12.0-124.13.1.el10_1, +28 more
    fixed: vendor fix RHSA-2025:21931
  • Red Hat Enterprise Linux BaseOS AUS (v. 8.2) perf 4.18.0-193.178.1.el8_2, kernel 4.18.0-193.178.1.el8_2, bpftool 4.18.0-193.178.1.el8_2, kernel-core 4.18.0-193.178.1.el8_2, kernel-tools 4.18.0-193.178.1.el8_2, python3-perf 4.18.0-193.178.1.el8_2, +8 more
    fixed: vendor fix RHSA-2025:23445
  • Red Hat Enterprise Linux BaseOS AUS (v.8.4) perf 4.18.0-305.182.1.el8_4, kernel 4.18.0-305.182.1.el8_4, bpftool 4.18.0-305.182.1.el8_4, kernel-core 4.18.0-305.182.1.el8_4, kernel-tools 4.18.0-305.182.1.el8_4, python3-perf 4.18.0-305.182.1.el8_4, +8 more
    fixed: vendor fix RHSA-2025:23463
  • Red Hat Enterprise Linux BaseOS AUS (v.8.6) perf 4.18.0-372.173.1.el8_6, kernel 4.18.0-372.173.1.el8_6, bpftool 4.18.0-372.173.1.el8_6, kernel-core 4.18.0-372.173.1.el8_6, kernel-tools 4.18.0-372.173.1.el8_6, python3-perf 4.18.0-372.173.1.el8_6, +8 more Red Hat Enterprise Linux BaseOS E4S (v.8.6) perf 4.18.0-372.173.1.el8_6, kernel 4.18.0-372.173.1.el8_6, bpftool 4.18.0-372.173.1.el8_6, kernel-core 4.18.0-372.173.1.el8_6, kernel-tools 4.18.0-372.173.1.el8_6, python3-perf 4.18.0-372.173.1.el8_6, +15 more
    fixed: vendor fix RHSA-2025:23425
  • Red Hat Enterprise Linux BaseOS E4S (v.8.8) perf 4.18.0-477.123.1.el8_8, kernel 4.18.0-477.123.1.el8_8, bpftool 4.18.0-477.123.1.el8_8, kernel-core 4.18.0-477.123.1.el8_8, kernel-tools 4.18.0-477.123.1.el8_8, python3-perf 4.18.0-477.123.1.el8_8, +9 more
    fixed: vendor fix RHSA-2025:23427
  • Red Hat Enterprise Linux BaseOS E4S (v.9.0) kernel 5.14.0-70.158.1.el9_0, bpftool 5.14.0-70.158.1.el9_0, kernel-core 5.14.0-70.158.1.el9_0, kernel-tools 5.14.0-70.158.1.el9_0, python3-perf 5.14.0-70.158.1.el9_0, kernel-modules 5.14.0-70.158.1.el9_0, +14 more
    fixed: vendor fix RHSA-2025:23426
  • Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool 7.0.0-284.150.1.el9_2, kernel 5.14.0-284.150.1.el9_2, kernel-64k 5.14.0-284.150.1.el9_2, kernel-core 5.14.0-284.150.1.el9_2, kernel-tools 5.14.0-284.150.1.el9_2, python3-perf 5.14.0-284.150.1.el9_2, +28 more
    fixed: vendor fix RHSA-2025:23423
  • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel 6.12.0-55.47.1.el10_0, kernel-64k 6.12.0-55.47.1.el10_0, kernel-core 6.12.0-55.47.1.el10_0, kernel-tools 6.12.0-55.47.1.el10_0, kernel-modules 6.12.0-55.47.1.el10_0, kernel-64k-core 6.12.0-55.47.1.el10_0, +27 more
    fixed: vendor fix RHSA-2025:22571
  • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool 7.3.0-427.103.1.el9_4, kernel 5.14.0-427.103.1.el9_4, kernel-64k 5.14.0-427.103.1.el9_4, kernel-core 5.14.0-427.103.1.el9_4, kernel-tools 5.14.0-427.103.1.el9_4, python3-perf 5.14.0-427.103.1.el9_4, +28 more
    fixed: vendor fix RHSA-2025:23450
  • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel 5.14.0-570.69.1.el9_6, kernel-64k 5.14.0-570.69.1.el9_6, kernel-core 5.14.0-570.69.1.el9_6, kernel-tools 5.14.0-570.69.1.el9_6, kernel-modules 5.14.0-570.69.1.el9_6, kernel-64k-core 5.14.0-570.69.1.el9_6, +27 more
    fixed: vendor fix RHSA-2025:22392
  • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) perf 4.18.0-305.182.1.el8_4, kernel 4.18.0-305.182.1.el8_4, bpftool 4.18.0-305.182.1.el8_4, kernel-core 4.18.0-305.182.1.el8_4, kernel-tools 4.18.0-305.182.1.el8_4, python3-perf 4.18.0-305.182.1.el8_4, +8 more
    fixed: vendor fix RHSA-2025:23463
  • Red Hat Enterprise Linux BaseOS TUS (v.8.6) perf 4.18.0-372.173.1.el8_6, kernel 4.18.0-372.173.1.el8_6, bpftool 4.18.0-372.173.1.el8_6, kernel-core 4.18.0-372.173.1.el8_6, kernel-tools 4.18.0-372.173.1.el8_6, python3-perf 4.18.0-372.173.1.el8_6, +8 more
    fixed: vendor fix RHSA-2025:23425
  • Red Hat Enterprise Linux BaseOS TUS (v.8.8) perf 4.18.0-477.123.1.el8_8, kernel 4.18.0-477.123.1.el8_8, bpftool 4.18.0-477.123.1.el8_8, kernel-core 4.18.0-477.123.1.el8_8, kernel-tools 4.18.0-477.123.1.el8_8, python3-perf 4.18.0-477.123.1.el8_8, +8 more
    fixed: vendor fix RHSA-2025:23427
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) libperf 5.14.0-611.11.1.el9_7, kernel-debuginfo-common-s390x 5.14.0-611.11.1.el9_7, kernel-debuginfo-common-x86_64 5.14.0-611.11.1.el9_7, kernel-debuginfo-common-aarch64 5.14.0-611.11.1.el9_7, kernel-debuginfo-common-ppc64le 5.14.0-611.11.1.el9_7
    fixed: vendor fix RHSA-2025:22405
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) libperf 6.12.0-124.13.1.el10_1, kernel-debuginfo-common-s390x 6.12.0-124.13.1.el10_1, kernel-debuginfo-common-x86_64 6.12.0-124.13.1.el10_1, kernel-debuginfo-common-aarch64 6.12.0-124.13.1.el10_1, kernel-debuginfo-common-ppc64le 6.12.0-124.13.1.el10_1
    fixed: vendor fix RHSA-2025:21931
  • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) libperf 6.12.0-55.47.1.el10_0, kernel-debuginfo-common-s390x 6.12.0-55.47.1.el10_0, kernel-debuginfo-common-x86_64 6.12.0-55.47.1.el10_0, kernel-debuginfo-common-aarch64 6.12.0-55.47.1.el10_0, kernel-debuginfo-common-ppc64le 6.12.0-55.47.1.el10_0
    fixed: vendor fix RHSA-2025:22571
  • Red Hat Enterprise Linux CRB (v. 8) kernel-debuginfo-common-x86_64 4.18.0-553.87.1.el8_10, kernel-debuginfo-common-aarch64 4.18.0-553.87.1.el8_10, kernel-debuginfo-common-ppc64le 4.18.0-553.87.1.el8_10
    fixed: vendor fix RHSA-2025:22388
  • Red Hat Enterprise Linux for Real Time (v. 7 ELS) kernel-rt 3.10.0-1160.144.1.rt56.1296.el7, kernel-rt-trace 3.10.0-1160.144.1.rt56.1296.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1160.144.1.rt56.1296.el7
    fixed: vendor fix RHSA-2025:23960
  • Red Hat Enterprise Linux NFV (v. 8) kernel-rt 4.18.0-553.87.1.rt7.428.el8_10, kernel-rt-kvm 4.18.0-553.87.1.rt7.428.el8_10, kernel-rt-core 4.18.0-553.87.1.rt7.428.el8_10, kernel-rt-modules 4.18.0-553.87.1.rt7.428.el8_10, kernel-rt-debug-kvm 4.18.0-553.87.1.rt7.428.el8_10, kernel-rt-debug-core 4.18.0-553.87.1.rt7.428.el8_10, +4 more
    fixed: vendor fix RHSA-2025:22387
  • Red Hat Enterprise Linux NFV E4S (v.9.0) kernel-rt 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-kvm 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-core 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-modules 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-debug-kvm 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-debug-core 5.14.0-70.158.1.rt21.230.el9_0, +4 more
    fixed: vendor fix RHSA-2025:23424
  • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt 5.14.0-611.11.1.el9_7, kernel-rt-64k 5.14.0-611.11.1.el9_7, kernel-rt-core 5.14.0-611.11.1.el9_7, kernel-rt-modules 5.14.0-611.11.1.el9_7, kernel-rt-64k-core 5.14.0-611.11.1.el9_7, kernel-rt-debug-core 5.14.0-611.11.1.el9_7, +14 more
    fixed: vendor fix RHSA-2025:22405
  • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt 6.12.0-124.13.1.el10_1, kernel-rt-64k 6.12.0-124.13.1.el10_1, kernel-rt-core 6.12.0-124.13.1.el10_1, kernel-rt-modules 6.12.0-124.13.1.el10_1, kernel-rt-64k-core 6.12.0-124.13.1.el10_1, kernel-rt-debug-core 6.12.0-124.13.1.el10_1, +14 more
    fixed: vendor fix RHSA-2025:21931
  • Red Hat Enterprise Linux Real Time E4S (v.9.0) kernel-rt 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-core 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-modules 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-debug-core 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-debug-modules 5.14.0-70.158.1.rt21.230.el9_0, kernel-rt-modules-extra 5.14.0-70.158.1.rt21.230.el9_0, +2 more
    fixed: vendor fix RHSA-2025:23424
  • Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt 5.14.0-284.150.1.rt14.435.el9_2, kernel-rt-core 5.14.0-284.150.1.rt14.435.el9_2, kernel-rt-modules 5.14.0-284.150.1.rt14.435.el9_2, kernel-rt-debug-core 5.14.0-284.150.1.rt14.435.el9_2, kernel-rt-modules-core 5.14.0-284.150.1.rt14.435.el9_2, kernel-rt-debug-modules 5.14.0-284.150.1.rt14.435.el9_2, +4 more
    fixed: vendor fix RHSA-2025:23422
  • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt 6.12.0-55.47.1.el10_0, kernel-rt-64k 6.12.0-55.47.1.el10_0, kernel-rt-core 6.12.0-55.47.1.el10_0, kernel-rt-modules 6.12.0-55.47.1.el10_0, kernel-rt-64k-core 6.12.0-55.47.1.el10_0, kernel-rt-debug-core 6.12.0-55.47.1.el10_0, +14 more
    fixed: vendor fix RHSA-2025:22571
  • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt 5.14.0-427.103.1.el9_4, kernel-rt-core 5.14.0-427.103.1.el9_4, kernel-rt-modules 5.14.0-427.103.1.el9_4, kernel-rt-debug-core 5.14.0-427.103.1.el9_4, kernel-rt-modules-core 5.14.0-427.103.1.el9_4, kernel-rt-debug-modules 5.14.0-427.103.1.el9_4, +4 more
    fixed: vendor fix RHSA-2025:23450
  • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt 5.14.0-570.69.1.el9_6, kernel-rt-64k 5.14.0-570.69.1.el9_6, kernel-rt-core 5.14.0-570.69.1.el9_6, kernel-rt-modules 5.14.0-570.69.1.el9_6, kernel-rt-64k-core 5.14.0-570.69.1.el9_6, kernel-rt-debug-core 5.14.0-570.69.1.el9_6, +14 more
    fixed: vendor fix RHSA-2025:22392

9 more fixed, 1 more not affected in the full advisory

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-26-295-11 updated cvss 7.0

Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.7 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.7
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-26-209-04 updated cvss 7.0

Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.6 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.6
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
4mo ago

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Linux
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.