CVE-2025-40347 json
net: enetc: fix the deadlock of enetc_mdio_lock
published 10mo ago modified 26d ago also EUVD-2025-203640
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
net: enetc: fix the deadlock of enetc_mdio_lock
After applying the workaround for err050089, the LS1028A platform experiences RCU stalls on RT kernel. This issue is caused by the recursive acquisition of the read lock enetc_mdio_lock. Here list some of the call stacks identified under the enetc_poll path that may lead to a deadlock:
enetc_poll -> enetc_lock_mdio -> enetc_clean_rx_ring OR napi_complete_done -> napi_gro_receive -> enetc_start_xmit -> enetc_lock_mdio -> enetc_map_tx_buffs -> enetc_unlock_mdio -> enetc_unlock_mdio
After enetc_poll acquires the read lock, a higher-priority writer attempts to acquire the lock, causing preemption. The writer detects that a read lock is already held and is scheduled out. However, readers under enetc_poll cannot acquire the read lock again because a writer is already waiting, leading to a thread hang.
Currently, the deadlock is avoided by adjusting enetc_lock_mdio to prevent recursive lock acquisition.
Patch / fix
- Linux Linux 5.11, 5.12, 6.1.175, 6.6.115, 6.12.56, 6.17.6, 6.18
- linux Debian 12 6.1.176-1
- linux Debian 13 6.12.57-1
- linux Debian 14 6.17.6-1
debian advisories DEBIAN-CVE-2025-40347
- linux Ubuntu 24.04 LTS 6.8.0-106.106
- linux Ubuntu 25.10 6.17.0-14.14
- linux-aws Ubuntu 24.04 LTS 6.8.0-1050.53
- linux-aws Ubuntu 25.10 6.17.0-1007.7
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1052.55
- linux-gcp Ubuntu 25.10 6.17.0-1007.7
- linux-gke Ubuntu 24.04 LTS 6.8.0-1048.53
- linux-ibm Ubuntu 24.04 LTS 6.8.0-1049.49
ubuntu advisories UBUNTU-CVE-2025-40347
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-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
- kernel-source-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
- kernel-source Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
- kernel-default Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
- kernel-kvmsmall Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
- kernel-default-base Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1.21.16
- kernel-rt Linux Micro 6.2 6.12.0-160000.9.1
- kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.9.1
suse advisories SUSE-SU-2026:20845-1SUSE-SU-2026:20876-1SUSE-SU-2026:20477-1SUSE-SU-2026:20498-1SUSE-SU-2026:20207-1SUSE-SU-2026:20220-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.9.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.9.1
opensuse advisories openSUSE-SU-2026:20145-1
- git.kernel.org/stable/c/a649161526736f48bcc592e3a412e5bcd7dd9e24 commit
- git.kernel.org/stable/c/2781ca82ce8cad263d80b617addb727e6a84c9e5 commit
- git.kernel.org/stable/c/1f92f5bd057a4fad9dab6af17963cdd21e5da6ed commit
- git.kernel.org/stable/c/2e55a49dc3b2a6b23329e4fbbd8a5feb20e220aa commit
- git.kernel.org/stable/c/50bd33f6b3922a6b760aa30d409cae891cec8fb5 commit
Is CVE-2025-40347 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2025-40347 updated cvss 5.5
kernel: net: enetc: fix the deadlock of enetc_mdio_lock
-
Red Hat Enterprise Linux 10 kernelaffected: no fix available “Fix deferred”
-
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 rv, perf, rtla, kernel, bpftool, libperf, +83 morenot 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
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/a649161526736f48bcc592e3a412e5bcd7dd9e24
- git.kernel.org /stable/c/2781ca82ce8cad263d80b617addb727e6a84c9e5
- git.kernel.org /stable/c/1f92f5bd057a4fad9dab6af17963cdd21e5da6ed
- git.kernel.org /stable/c/2e55a49dc3b2a6b23329e4fbbd8a5feb20e220aa
- git.kernel.org /stable/c/50bd33f6b3922a6b760aa30d409cae891cec8fb5
Sources
- CVE List CVE-2025-40347
- NVD CVE-2025-40347
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.