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Fencer Vulns
high 7.8

CVE-2025-38154 json

bpf, sockmap: Avoid using sk_socket after free when sending

published 2025-07-03 16 mo ago modified 2026-10-15 24 d ago also EUVD-2025-19790

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 8%
public exploits
0
none known

Summary

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

bpf, sockmap: Avoid using sk_socket after free when sending

The sk->sk_socket is not locked or referenced in backlog thread, and during the call to skb_send_sock(), there is a race condition with the release of sk_socket. All types of sockets(tcp/udp/unix/vsock) will be affected.

Race conditions: ''' CPU0 CPU1

backlog::skb_send_sock sendmsg_unlocked sock_sendmsg sock_sendmsg_nosec close(fd): ... ops->release() -> sock_map_close() sk_socket->ops = NULL free(socket) sock->ops->sendmsg ^ panic here '''

The ref of psock become 0 after sock_map_close() executed. ''' void sock_map_close() { ... if (likely(psock)) { ... // !! here we remove psock and the ref of psock become 0 sock_map_remove_links(sk, psock) psock = sk_psock_get(sk); if (unlikely(!psock)) goto no_psock; <=== Control jumps here via goto ... cancel_delayed_work_sync(&psock->work); <=== not executed sk_psock_put(sk, psock); ... } '''

Based on the fact that we already wait for the workqueue to finish in sock_map_close() if psock is held, we simply increase the psock reference count to avoid race conditions.

With this patch, if the backlog thread is running, sock_map_close() will wait for the backlog thread to complete and cancel all pending work.

If no backlog running, any pending work that hasn't started by then will fail when invoked by sk_psock_get(), as the psock reference count have been zeroed, and sk_psock_drop() will cancel all jobs via cancel_delayed_work_sync().

In summary, we require synchronization to coordinate the backlog thread and close() thread.

The panic I catched: ''' Workqueue: events sk_psock_backlog RIP: 0010:sock_sendmsg+0x21d/0x440 RAX: 0000000000000000 RBX: ffffc9000521fad8 RCX: 0000000000000001 ... Call Trace: <TASK> ? die_addr+0x40/0xa0 ? exc_general_protection+0x14c/0x230 ? asm_exc_general_protection+0x26/0x30 ? sock_sendmsg+0x21d/0x440 ? sock_sendmsg+0x3e0/0x440 ? __pfx_sock_sendmsg+0x10/0x10 __skb_send_sock+0x543/0xb70 sk_psock_backlog+0x247/0xb80 ... '''

Patch / fix

  • Linux Linux 5.15.186, 6.1.142, 6.6.94, 6.10, 6.12.34, 6.15.3, 6.16
  • linux Debian 12 6.1.147-1
  • linux Debian 14, Debian 13 6.12.35-1

debian advisories DEBIAN-CVE-2025-38154

  • linux Ubuntu 22.04 LTS 5.15.0-156.166
  • linux Ubuntu 24.04 LTS 6.8.0-100.100
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1092.99
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1046.49
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1092.101
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1047.50
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1089.95
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1043.48

ubuntu advisories UBUNTU-CVE-2025-38154

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 enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • rv enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • perf enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • rtla enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • libperf enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • kernel-rt enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • kernel-64k enterprise linux eus 10.0 6.12.0-55.82.1.el10_0
  • kernel-core enterprise linux eus 10.0 6.12.0-55.82.1.el10_0

red hat advisories RHSA-2026:27731RHSA-2026:7100RHSA-2026:7013RHSA-2026:6310RHSA-2026:5813RHSA-2026:5690

  • kernel-rt Linux Micro 6.2 6.12.0-160000.6.1
  • kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.6.1
  • kernel-source SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.6.1
  • kernel-default SLES 16.0, SLE High Availability Extension 16.0, Linux Micro 6.2 +1 more 6.12.0-160000.6.1
  • kernel-default-base SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.6.1.160000.2.4
  • kernel-syms SLES 16.0, Linux Micro Extras 6.2, SLES for SAP applications 16.0 6.12.0-160000.6.1
  • kernel-obs-qa SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.6.1
  • kernel-kvmsmall SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.6.1

suse advisories SUSE-SU-2025:21074-1SUSE-SU-2025:21139-1SUSE-SU-2026:20560-1SUSE-SU-2025:21179-1SUSE-SU-2025:03023-1SUSE-SU-2025:03011-1

  • kernel-rt openSUSE Leap 16.0 6.12.0-160000.6.1
  • dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.6.1
  • kernel-64kb openSUSE Leap 16.0 6.12.0-160000.6.1
  • kernel-syms openSUSE Leap 16.0 6.12.0-160000.6.1
  • kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.6.1
  • kernel-source openSUSE Leap 16.0 6.12.0-160000.6.1
  • kernel-default openSUSE Leap 16.0 6.12.0-160000.6.1
  • kernel-kvmsmall openSUSE Leap 16.0 6.12.0-160000.6.1

opensuse advisories openSUSE-SU-2025:20081-1

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-2025-38154 updated cvss 6.7

kernel: Linux kernel: Use-after-free in BPF sockmap can lead to denial of service and privilege escalation

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
    affected: no fix available
  • Red Hat CodeReady Linux Builder EUS (v.9.4) libperf 5.14.0-427.117.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.117.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.117.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.117.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.117.1.el9_4
    fixed: vendor fix RHSA-2026:6310
  • Red Hat CodeReady Linux Builder EUS (v.9.6) libperf 5.14.0-570.94.1.el9_6, kernel-debuginfo-common-s390x 5.14.0-570.94.1.el9_6, kernel-debuginfo-common-x86_64 5.14.0-570.94.1.el9_6, kernel-debuginfo-common-aarch64 5.14.0-570.94.1.el9_6, kernel-debuginfo-common-ppc64le 5.14.0-570.94.1.el9_6
    fixed: vendor fix RHSA-2026:3520
  • Red Hat Enterprise Linux AppStream E4S (v.9.0) perf 5.14.0-70.173.1.el9_0, kernel-devel-matched 5.14.0-70.173.1.el9_0, kernel-debug-devel-matched 5.14.0-70.173.1.el9_0, kernel-debuginfo-common-s390x 5.14.0-70.173.1.el9_0, kernel-zfcpdump-devel-matched 5.14.0-70.173.1.el9_0, kernel-debuginfo-common-x86_64 5.14.0-70.173.1.el9_0, +2 more
    fixed: vendor fix RHSA-2026:7013
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) perf 5.14.0-284.161.1.el9_2, rtla 5.14.0-284.161.1.el9_2, kernel-devel-matched 5.14.0-284.161.1.el9_2, kernel-64k-devel-matched 5.14.0-284.161.1.el9_2, kernel-debug-devel-matched 5.14.0-284.161.1.el9_2, kernel-debuginfo-common-s390x 5.14.0-284.161.1.el9_2, +5 more
    fixed: vendor fix RHSA-2026:5813
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) rv 6.12.0-55.82.1.el10_0, perf 6.12.0-55.82.1.el10_0, rtla 6.12.0-55.82.1.el10_0, python3-perf 6.12.0-55.82.1.el10_0, kernel-devel-matched 6.12.0-55.82.1.el10_0, kernel-64k-devel-matched 6.12.0-55.82.1.el10_0, +7 more
    fixed: vendor fix RHSA-2026:27731
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) rv 5.14.0-427.117.1.el9_4, perf 5.14.0-427.117.1.el9_4, rtla 5.14.0-427.117.1.el9_4, kernel-devel-matched 5.14.0-427.117.1.el9_4, kernel-64k-devel-matched 5.14.0-427.117.1.el9_4, kernel-debug-devel-matched 5.14.0-427.117.1.el9_4, +6 more
    fixed: vendor fix RHSA-2026:6310
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) rv 5.14.0-570.94.1.el9_6, perf 5.14.0-570.94.1.el9_6, rtla 5.14.0-570.94.1.el9_6, python3-perf 5.14.0-570.94.1.el9_6, kernel-devel-matched 5.14.0-570.94.1.el9_6, kernel-64k-devel-matched 5.14.0-570.94.1.el9_6, +7 more
    fixed: vendor fix RHSA-2026:3520
show 16 more
  • Red Hat Enterprise Linux BaseOS E4S (v.9.0) kernel 5.14.0-70.173.1.el9_0, bpftool 5.14.0-70.173.1.el9_0, kernel-core 5.14.0-70.173.1.el9_0, kernel-tools 5.14.0-70.173.1.el9_0, python3-perf 5.14.0-70.173.1.el9_0, kernel-modules 5.14.0-70.173.1.el9_0, +14 more
    fixed: vendor fix RHSA-2026:7013
  • Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool 7.0.0-284.161.1.el9_2, kernel 5.14.0-284.161.1.el9_2, kernel-64k 5.14.0-284.161.1.el9_2, kernel-core 5.14.0-284.161.1.el9_2, kernel-tools 5.14.0-284.161.1.el9_2, python3-perf 5.14.0-284.161.1.el9_2, +28 more
    fixed: vendor fix RHSA-2026:5813
  • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel 6.12.0-55.82.1.el10_0, kernel-64k 6.12.0-55.82.1.el10_0, kernel-core 6.12.0-55.82.1.el10_0, kernel-tools 6.12.0-55.82.1.el10_0, kernel-modules 6.12.0-55.82.1.el10_0, kernel-64k-core 6.12.0-55.82.1.el10_0, +27 more
    fixed: vendor fix RHSA-2026:27731
  • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool 7.3.0-427.117.1.el9_4, kernel 5.14.0-427.117.1.el9_4, kernel-64k 5.14.0-427.117.1.el9_4, kernel-core 5.14.0-427.117.1.el9_4, kernel-tools 5.14.0-427.117.1.el9_4, python3-perf 5.14.0-427.117.1.el9_4, +28 more
    fixed: vendor fix RHSA-2026:6310
  • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel 5.14.0-570.94.1.el9_6, kernel-64k 5.14.0-570.94.1.el9_6, kernel-core 5.14.0-570.94.1.el9_6, kernel-tools 5.14.0-570.94.1.el9_6, kernel-modules 5.14.0-570.94.1.el9_6, kernel-64k-core 5.14.0-570.94.1.el9_6, +27 more
    fixed: vendor fix RHSA-2026:3520
  • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) libperf 6.12.0-55.82.1.el10_0, kernel-debuginfo-common-s390x 6.12.0-55.82.1.el10_0, kernel-debuginfo-common-x86_64 6.12.0-55.82.1.el10_0, kernel-debuginfo-common-aarch64 6.12.0-55.82.1.el10_0, kernel-debuginfo-common-ppc64le 6.12.0-55.82.1.el10_0
    fixed: vendor fix RHSA-2026:27731
  • Red Hat Enterprise Linux NFV E4S (v.9.0) kernel-rt 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-kvm 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-core 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-modules 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-debug-kvm 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-debug-core 5.14.0-70.173.1.rt21.245.el9_0, +4 more Red Hat Enterprise Linux Real Time E4S (v.9.0) kernel-rt 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-core 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-modules 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-debug-core 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-debug-modules 5.14.0-70.173.1.rt21.245.el9_0, kernel-rt-modules-extra 5.14.0-70.173.1.rt21.245.el9_0, +2 more
    fixed: vendor fix RHSA-2026:7100
  • Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-core 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-modules 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-debug-core 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-modules-core 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-debug-modules 5.14.0-284.161.1.rt14.446.el9_2, +4 more
    fixed: vendor fix RHSA-2026:5690
  • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt 6.12.0-55.82.1.el10_0, kernel-rt-64k 6.12.0-55.82.1.el10_0, kernel-rt-core 6.12.0-55.82.1.el10_0, kernel-rt-modules 6.12.0-55.82.1.el10_0, kernel-rt-64k-core 6.12.0-55.82.1.el10_0, kernel-rt-debug-core 6.12.0-55.82.1.el10_0, +14 more
    fixed: vendor fix RHSA-2026:27731
  • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt 5.14.0-427.117.1.el9_4, kernel-rt-core 5.14.0-427.117.1.el9_4, kernel-rt-modules 5.14.0-427.117.1.el9_4, kernel-rt-debug-core 5.14.0-427.117.1.el9_4, kernel-rt-modules-core 5.14.0-427.117.1.el9_4, kernel-rt-debug-modules 5.14.0-427.117.1.el9_4, +4 more
    fixed: vendor fix RHSA-2026:6310
  • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt 5.14.0-570.94.1.el9_6, kernel-rt-64k 5.14.0-570.94.1.el9_6, kernel-rt-core 5.14.0-570.94.1.el9_6, kernel-rt-modules 5.14.0-570.94.1.el9_6, kernel-rt-64k-core 5.14.0-570.94.1.el9_6, kernel-rt-debug-core 5.14.0-570.94.1.el9_6, +14 more
    fixed: vendor fix RHSA-2026:3520
  • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-kvm 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-core 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-modules 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-debug-kvm 5.14.0-284.161.1.rt14.446.el9_2, kernel-rt-debug-core 5.14.0-284.161.1.rt14.446.el9_2, +6 more
    fixed: vendor fix RHSA-2026:5690
  • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt 6.12.0-55.82.1.el10_0, kernel-rt-kvm 6.12.0-55.82.1.el10_0, kernel-rt-core 6.12.0-55.82.1.el10_0, kernel-rt-modules 6.12.0-55.82.1.el10_0, kernel-rt-debug-kvm 6.12.0-55.82.1.el10_0, kernel-rt-debug-core 6.12.0-55.82.1.el10_0, +6 more
    fixed: vendor fix RHSA-2026:27731
  • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt 5.14.0-427.117.1.el9_4, kernel-rt-kvm 5.14.0-427.117.1.el9_4, kernel-rt-core 5.14.0-427.117.1.el9_4, kernel-rt-modules 5.14.0-427.117.1.el9_4, kernel-rt-debug-kvm 5.14.0-427.117.1.el9_4, kernel-rt-debug-core 5.14.0-427.117.1.el9_4, +6 more
    fixed: vendor fix RHSA-2026:6310
  • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt 5.14.0-570.94.1.el9_6, kernel-rt-kvm 5.14.0-570.94.1.el9_6, kernel-rt-core 5.14.0-570.94.1.el9_6, kernel-rt-modules 5.14.0-570.94.1.el9_6, kernel-rt-debug-kvm 5.14.0-570.94.1.el9_6, kernel-rt-debug-core 5.14.0-570.94.1.el9_6, +6 more
    fixed: vendor fix RHSA-2026:3520
  • 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
    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 SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
24 d ago

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% 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
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

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.