7.1

CVE-2026-23204: net/sched: cls_u32: use skb_header_pointer_careful()

Modified
AliasesUBUNTU-CVE-2026-23204DEBIAN-CVE-2026-23204
Published 14-02-2026Last modified 19-10-2026

Vulnerability summary

CVE-2026-23204 is a high (CVSS 7.1) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 4.4% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.1, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.15%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 60 · Related 39
DSA-6141-1MGASA-2026-0097MGASA-2026-0098OPENSUSE-SU-2026:20572-1RHSA-2026:10108RHSA-2026:10756

Timeline

  1. 14-02-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_u32: use skb_header_pointer_careful() skb_header_pointer() does not fully validate negative @offset values. Use skb_header_pointer_careful() instead. GangMin Kim provided a report and a repro fooling u32_classify(): BUG: KASAN: slab-out-of-bounds in u32_classify+0x1180/0x11b0 net/sched/cls_u32.c:221

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 0.13% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu157 products
  • linuxAll versions (No fix recorded) | < 5.15.0-186.196 | < 6.8.0-117.117
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1112.119 | < 6.8.0-1055.58
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < 66e4b63d61c15de6ca5332d9ca6db59a404d7136 | ≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < 29681ed51e737be14d18ecd1c304c57002e4b72c | ≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < cfa745830e45ecb75c061aa34330ee0cac941cc7 | ≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < 13336a6239b9d7c6e61483017bb8bdfe3ceb10a5 | ≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < e41a23e61259f5526af875c3b86b3d42a9bae0e5 | ≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < 8a672f177ebe19c93d795fbe967846084fbc7943 | ≥ fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d, < cabd1a976375780dabab888784e356f574bbaed8 | 2.6.35
  • linux_kernel≥ 2.6.35.1, < 6.6.124 | ≥ 6.7, < 6.12.70 | ≥ 6.13, < 6.18.10 | 2.6.35 | 2.6.35:rc2 | 2.6.35:rc3 | 2.6.35:rc4 | 2.6.35:rc5 | 2.6.35:rc6 | 6.19:rc1 | 6.19:rc2 | 6.19:rc3 | 6.19:rc4 | 6.19:rc5 | 6.19:rc6 | 6.19:rc7 | 6.19:rc8
Debian1 product
  • linux< 6.1.170-1 | < 6.12.73-1 | < 6.18.10-1

3 vendors · 160 products

References

38 links
Show all 38 references