01 Record

CVE-2026-74656

ipv4: fix use-after-free in fib_nhc_update_mtu()

HighPUBLISHEDCNA: Linux

CNA base score7.8 CVSS v3.xCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

View raw JSON

02 Description

ipv4: fix use-after-free in fib_nhc_update_mtu()

03 Exploitation and scoring

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.12% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 1.9% of scored records. A rank, not a probability.

NVD base score

7.8 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

NVD analysis status

Received. NVD last modified this record on 2026-10-16.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published

2026-08-22 15:32Z2 MO AGO

Last updated

2026-10-16 19:16Z12 DAYS AGO

Reserved

2026-08-15

Assigning CNA

Linux

Record state

PUBLISHED

Severity

High (CVSS 7.8)

CNA CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses

CWE-367Time-of-check Time-of-use (TOCTOU) Race ConditionBase

Data version

5.2

Document digest

14eb1d76c5d01ce05586d46e817704571222339ca8ab36168d469860dadc316d

05 Affected products

VendorProductVersionsPlatforms

LinuxLinuxaf7d6cce53694a88d6a1bb60c9a239a6a5144459 to < fd39e711866498ae94fcf9acf6f422a4f045b681, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < e1e602d6b22d5cb1641c4459c487eb18bf569e0a, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < e00f7d2b5f2540a3415a229c982af7a25ff6362e, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < dfe388da13aa784851e5ebbea90afbb099075761, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < 5a28a4b22dde92f9d293b94236314b8d6181dc4a, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < 63996ffc594d128ccec8fc0983f91effd2d3adc4, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < ed503eaad62f20cdd5122d7c3078a648a99c8f16, af7d6cce53694a88d6a1bb60c9a239a6a5144459 to < bc5bde9ce3cc36502839dfe98e068f7303a50982, b427832009b97a3ee412ef643a80b15372a7754d, 2b7e4c735933be79882aba2bed9afa789e03c62f, 8d59c3a6376bbc6dd3f7303968a719ffba75a4f1, 9b4869cf385aa16f89c0f019eed4ec4e36aa441c, ff34695ced21e2dfa04d0fa1c5f6c35011fa8117, 3.16.62 to < 3.17, 4.4.162 to < 4.5, 4.9.134 to < 4.10, 4.14.77 to < 4.15, 4.18.15 to < 4.19, 4.19—

06 References

git.kernel.orghttps://git.kernel.org/stable/c/fd39e711866498ae94fcf9acf6f422a4f045b681
git.kernel.orghttps://git.kernel.org/stable/c/e1e602d6b22d5cb1641c4459c487eb18bf569e0a
git.kernel.orghttps://git.kernel.org/stable/c/e00f7d2b5f2540a3415a229c982af7a25ff6362e
git.kernel.orghttps://git.kernel.org/stable/c/dfe388da13aa784851e5ebbea90afbb099075761
git.kernel.orghttps://git.kernel.org/stable/c/5a28a4b22dde92f9d293b94236314b8d6181dc4a
git.kernel.orghttps://git.kernel.org/stable/c/63996ffc594d128ccec8fc0983f91effd2d3adc4
git.kernel.orghttps://git.kernel.org/stable/c/ed503eaad62f20cdd5122d7c3078a648a99c8f16
git.kernel.orghttps://git.kernel.org/stable/c/bc5bde9ce3cc36502839dfe98e068f7303a50982

07 Fixed in

Debian 12

linux
Fixed in 6.1.187-1
linux-6.12
Fixed in 6.12.107-1~deb12u1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 13

linux
Fixed in 6.12.105-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

linux
Fixed in 7.1.9-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.