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Fencer Vulns
high 7.8

CVE-2025-21867 json

bpf, test_run: Fix use-after-free issue in eth_skb_pkt_type()

published 2025-03-27 19 mo ago modified 2026-10-15 25 d ago also EUVD-2025-8435

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 11%
public exploits
0
none known

Summary

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

bpf, test_run: Fix use-after-free issue in eth_skb_pkt_type()

KMSAN reported a use-after-free issue in eth_skb_pkt_type()[1]. The cause of the issue was that eth_skb_pkt_type() accessed skb's data that didn't contain an Ethernet header. This occurs when bpf_prog_test_run_xdp() passes an invalid value as the user_data argument to bpf_test_init().

Fix this by returning an error when user_data is less than ETH_HLEN in bpf_test_init(). Additionally, remove the check for "if (user_size > size)" as it is unnecessary.

[1] BUG: KMSAN: use-after-free in eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] BUG: KMSAN: use-after-free in eth_type_trans+0x4ee/0x980 net/ethernet/eth.c:165 eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] eth_type_trans+0x4ee/0x980 net/ethernet/eth.c:165 __xdp_build_skb_from_frame+0x5a8/0xa50 net/core/xdp.c:635 xdp_recv_frames net/bpf/test_run.c:272 [inline] xdp_test_run_batch net/bpf/test_run.c:361 [inline] bpf_test_run_xdp_live+0x2954/0x3330 net/bpf/test_run.c:390 bpf_prog_test_run_xdp+0x148e/0x1b10 net/bpf/test_run.c:1318 bpf_prog_test_run+0x5b7/0xa30 kernel/bpf/syscall.c:4371 __sys_bpf+0x6a6/0xe20 kernel/bpf/syscall.c:5777 __do_sys_bpf kernel/bpf/syscall.c:5866 [inline] __se_sys_bpf kernel/bpf/syscall.c:5864 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5864 x64_sys_call+0x2ea0/0x3d90 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at: free_pages_prepare mm/page_alloc.c:1056 [inline] free_unref_page+0x156/0x1320 mm/page_alloc.c:2657 __free_pages+0xa3/0x1b0 mm/page_alloc.c:4838 bpf_ringbuf_free kernel/bpf/ringbuf.c:226 [inline] ringbuf_map_free+0xff/0x1e0 kernel/bpf/ringbuf.c:235 bpf_map_free kernel/bpf/syscall.c:838 [inline] bpf_map_free_deferred+0x17c/0x310 kernel/bpf/syscall.c:862 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa2b/0x1b60 kernel/workqueue.c:3310 worker_thread+0xedf/0x1550 kernel/workqueue.c:3391 kthread+0x535/0x6b0 kernel/kthread.c:389 ret_from_fork+0x6e/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

CPU: 1 UID: 0 PID: 17276 Comm: syz.1.16450 Not tainted 6.12.0-05490-g9bb88c659673 #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014

Patch / fix

  • Linux Linux 6.1.130, 6.6.80, 6.12.17, 6.13.5, 6.14
  • linux Debian 12 6.1.133-1
  • linux Debian 14, Debian 13 6.12.17-1

debian advisories DEBIAN-CVE-2025-21867

  • linux Ubuntu 24.04 LTS 6.8.0-78.78
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1035.37
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1036.38
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1032.36
  • linux-ibm Ubuntu 24.04 LTS 6.8.0-1033.33
  • linux-azure Ubuntu 24.04 LTS 6.8.0-1034.39
  • linux-gkeop Ubuntu 24.04 LTS 6.8.0-1019.21
  • linux-raspi Ubuntu 24.04 LTS 6.8.0-1035.39

ubuntu advisories UBUNTU-CVE-2025-21867

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 10.0 6.12.0-55.28.1.el10_0
  • rv RHEL 10.0 6.12.0-55.28.1.el10_0
  • perf RHEL 10.0 6.12.0-55.28.1.el10_0
  • rtla RHEL 10.0 6.12.0-55.28.1.el10_0
  • libperf RHEL 10.0 6.12.0-55.28.1.el10_0
  • kernel-rt RHEL 10.0 6.12.0-55.28.1.el10_0
  • kernel-64k RHEL 10.0 6.12.0-55.28.1.el10_0
  • kernel-core RHEL 10.0 6.12.0-55.28.1.el10_0

red hat advisories RHSA-2025:15016RHSA-2025:14696RHSA-2025:14691RHSA-2025:14009RHSA-2025:13962RHSA-2023:2458

  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.3.1
  • kernel-syms-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.3.1
  • kernel-source-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.3.1
  • kernel-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-syms-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-rt_debug Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-source-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.3.1

suse advisories SUSE-SU-2025:01967-1SUSE-SU-2025:01964-1SUSE-SU-2025:01951-1SUSE-SU-2025:01919-1SUSE-SU-2025:01707-1SUSE-SU-2025:20344-1

  • kernel AlmaLinux 9 5.14.0-570.35.1.el9_6
  • rv AlmaLinux 9 5.14.0-570.35.1.el9_6
  • perf AlmaLinux 9 5.14.0-570.35.1.el9_6
  • rtla AlmaLinux 9 5.14.0-570.35.1.el9_6
  • libperf AlmaLinux 9 5.14.0-570.35.1.el9_6
  • kernel-rt AlmaLinux 9 5.14.0-570.35.1.el9_6
  • kernel-64k AlmaLinux 9 5.14.0-570.35.1.el9_6
  • kernel-core AlmaLinux 9 5.14.0-570.35.1.el9_6

almalinux advisories ALSA-2025:13962ALSA-2025:14009

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-2025-21867 updated cvss 7.0

kernel: bpf, test_run: Fix use-after-free issue in eth_skb_pkt_type()

  • Red Hat CodeReady Linux Builder EUS (v.9.4) libperf 5.14.0-427.85.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.85.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.85.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.85.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.85.1.el9_4
    fixed: vendor fix RHSA-2025:15016
  • Red Hat Enterprise Linux AppStream (v. 9) rv 5.14.0-570.35.1.el9_6, perf 5.14.0-284.11.1.el9_2, perf 5.14.0-570.35.1.el9_6, rtla 5.14.0-284.11.1.el9_2, rtla 5.14.0-570.35.1.el9_6, python3-perf 5.14.0-570.35.1.el9_6, +18 more
    fixed: vendor fix RHSA-2023:2458
  • Red Hat Enterprise Linux AppStream (v. 10) rv 6.12.0-55.28.1.el10_0, perf 6.12.0-55.28.1.el10_0, rtla 6.12.0-55.28.1.el10_0, python3-perf 6.12.0-55.28.1.el10_0, kernel-devel-matched 6.12.0-55.28.1.el10_0, kernel-64k-devel-matched 6.12.0-55.28.1.el10_0, +7 more
    fixed: vendor fix RHSA-2025:14009
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) perf 5.14.0-284.134.1.el9_2, rtla 5.14.0-284.134.1.el9_2, kernel-devel-matched 5.14.0-284.134.1.el9_2, kernel-64k-devel-matched 5.14.0-284.134.1.el9_2, kernel-debug-devel-matched 5.14.0-284.134.1.el9_2, kernel-debuginfo-common-s390x 5.14.0-284.134.1.el9_2, +5 more
    fixed: vendor fix RHSA-2025:14696
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) rv 5.14.0-427.85.1.el9_4, perf 5.14.0-427.85.1.el9_4, rtla 5.14.0-427.85.1.el9_4, kernel-devel-matched 5.14.0-427.85.1.el9_4, kernel-64k-devel-matched 5.14.0-427.85.1.el9_4, kernel-debug-devel-matched 5.14.0-427.85.1.el9_4, +6 more
    fixed: vendor fix RHSA-2025:15016
  • Red Hat Enterprise Linux BaseOS (v. 9) bpftool 7.0.0-284.11.1.el9_2, kernel 5.14.0-284.11.1.el9_2, kernel 5.14.0-570.35.1.el9_6, kernel-64k 5.14.0-284.11.1.el9_2, kernel-64k 5.14.0-570.35.1.el9_6, kernel-core 5.14.0-284.11.1.el9_2, +61 more
    fixed: vendor fix RHSA-2023:2458
  • Red Hat Enterprise Linux BaseOS (v. 10) kernel 6.12.0-55.28.1.el10_0, kernel-64k 6.12.0-55.28.1.el10_0, kernel-core 6.12.0-55.28.1.el10_0, kernel-tools 6.12.0-55.28.1.el10_0, kernel-modules 6.12.0-55.28.1.el10_0, kernel-64k-core 6.12.0-55.28.1.el10_0, +27 more
    fixed: vendor fix RHSA-2025:14009
  • Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool 7.0.0-284.134.1.el9_2, kernel 5.14.0-284.134.1.el9_2, kernel-64k 5.14.0-284.134.1.el9_2, kernel-core 5.14.0-284.134.1.el9_2, kernel-tools 5.14.0-284.134.1.el9_2, python3-perf 5.14.0-284.134.1.el9_2, +28 more
    fixed: vendor fix RHSA-2025:14696
show 13 more
  • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool 7.3.0-427.85.1.el9_4, kernel 5.14.0-427.85.1.el9_4, kernel-64k 5.14.0-427.85.1.el9_4, kernel-core 5.14.0-427.85.1.el9_4, kernel-tools 5.14.0-427.85.1.el9_4, python3-perf 5.14.0-427.85.1.el9_4, +28 more
    fixed: vendor fix RHSA-2025:15016
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) libperf 5.14.0-570.35.1.el9_6, kernel-debuginfo-common-s390x 5.14.0-570.35.1.el9_6, kernel-debuginfo-common-x86_64 5.14.0-570.35.1.el9_6, kernel-debuginfo-common-aarch64 5.14.0-570.35.1.el9_6, kernel-debuginfo-common-ppc64le 5.14.0-570.35.1.el9_6
    fixed: vendor fix RHSA-2025:13962
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) libperf 6.12.0-55.28.1.el10_0, kernel-debuginfo-common-s390x 6.12.0-55.28.1.el10_0, kernel-debuginfo-common-x86_64 6.12.0-55.28.1.el10_0, kernel-debuginfo-common-aarch64 6.12.0-55.28.1.el10_0, kernel-debuginfo-common-ppc64le 6.12.0-55.28.1.el10_0
    fixed: vendor fix RHSA-2025:14009
  • Red Hat Enterprise Linux CRB (v. 9) kernel-debuginfo-common-s390x 5.14.0-284.11.1.el9_2, kernel-debuginfo-common-x86_64 5.14.0-284.11.1.el9_2, kernel-debuginfo-common-aarch64 5.14.0-284.11.1.el9_2, kernel-debuginfo-common-ppc64le 5.14.0-284.11.1.el9_2
    fixed: vendor fix RHSA-2023:2458
  • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt 5.14.0-570.35.1.el9_6, kernel-rt-64k 5.14.0-570.35.1.el9_6, kernel-rt-core 5.14.0-570.35.1.el9_6, kernel-rt-modules 5.14.0-570.35.1.el9_6, kernel-rt-64k-core 5.14.0-570.35.1.el9_6, kernel-rt-debug-core 5.14.0-570.35.1.el9_6, +14 more
    fixed: vendor fix RHSA-2025:13962
  • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt 6.12.0-55.28.1.el10_0, kernel-rt-64k 6.12.0-55.28.1.el10_0, kernel-rt-core 6.12.0-55.28.1.el10_0, kernel-rt-modules 6.12.0-55.28.1.el10_0, kernel-rt-64k-core 6.12.0-55.28.1.el10_0, kernel-rt-debug-core 6.12.0-55.28.1.el10_0, +14 more
    fixed: vendor fix RHSA-2025:14009
  • Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-core 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-modules 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-debug-core 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-modules-core 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-debug-modules 5.14.0-284.134.1.rt14.419.el9_2, +4 more
    fixed: vendor fix RHSA-2025:14691
  • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt 5.14.0-427.85.1.el9_4, kernel-rt-core 5.14.0-427.85.1.el9_4, kernel-rt-modules 5.14.0-427.85.1.el9_4, kernel-rt-debug-core 5.14.0-427.85.1.el9_4, kernel-rt-modules-core 5.14.0-427.85.1.el9_4, kernel-rt-debug-modules 5.14.0-427.85.1.el9_4, +4 more
    fixed: vendor fix RHSA-2025:15016
  • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt 5.14.0-570.35.1.el9_6, kernel-rt-kvm 5.14.0-570.35.1.el9_6, kernel-rt-core 5.14.0-570.35.1.el9_6, kernel-rt-modules 5.14.0-570.35.1.el9_6, kernel-rt-debug-kvm 5.14.0-570.35.1.el9_6, kernel-rt-debug-core 5.14.0-570.35.1.el9_6, +6 more
    fixed: vendor fix RHSA-2025:13962
  • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt 6.12.0-55.28.1.el10_0, kernel-rt-kvm 6.12.0-55.28.1.el10_0, kernel-rt-core 6.12.0-55.28.1.el10_0, kernel-rt-modules 6.12.0-55.28.1.el10_0, kernel-rt-debug-kvm 6.12.0-55.28.1.el10_0, kernel-rt-debug-core 6.12.0-55.28.1.el10_0, +6 more
    fixed: vendor fix RHSA-2025:14009
  • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-kvm 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-core 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-modules 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-debug-kvm 5.14.0-284.134.1.rt14.419.el9_2, kernel-rt-debug-core 5.14.0-284.134.1.rt14.419.el9_2, +6 more
    fixed: vendor fix RHSA-2025:14691
  • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt 5.14.0-427.85.1.el9_4, kernel-rt-kvm 5.14.0-427.85.1.el9_4, kernel-rt-core 5.14.0-427.85.1.el9_4, kernel-rt-modules 5.14.0-427.85.1.el9_4, kernel-rt-debug-kvm 5.14.0-427.85.1.el9_4, kernel-rt-debug-core 5.14.0-427.85.1.el9_4, +6 more
    fixed: vendor fix RHSA-2025:15016
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more 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
    not affected: vulnerable code not present

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 7.8

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 7.8

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
19 mo ago

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

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

Weakness
Technology feeds

References

Sources

Fencer Vulns 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.