5.5

CVE-2026-43036: linux Use of Uninitialized Resource

CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2026-43036DEBIAN-CVE-2026-43036
Published 01-05-2026Last modified 21-10-2026
Open JSON

Vulnerability summary

CVE-2026-43036 is a medium (CVSS 5.5) Use of Uninitialized Resource vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.8% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.12%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 26 · Related 26
OPENSUSE-SU-2026:21388-1SUSE-SU-2026:22433-1SUSE-SU-2026:22436-1SUSE-SU-2026:22458-1SUSE-SU-2026:22460-1SUSE-SU-2026:22742-1

Timeline

  1. 01-05-2026
    PublishedVulnerability first disclosed.
  2. 21-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header offsets that are not always safe for direct dereference on packets injected from PF_PACKET paths. Use skb_header_pointer() for the TCPv4 frag_off check so the header read is robust whether data is already linear or needs copying. [1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.12%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

0.00 pp

From 0.12% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.12%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu156 products
  • linuxAll versions (No fix recorded) | < 6.8.0-136.136
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 6.8.0-1061.64
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ cbc53e08a793b073e79f42ca33f1f3568703540d, < 5057502630fbc8ce468ff617ff59af275960b537 | ≥ cbc53e08a793b073e79f42ca33f1f3568703540d, < f7a6cd508e9e825a2c69fa9e13d41ee156852f25 | ≥ cbc53e08a793b073e79f42ca33f1f3568703540d, < cc91202fc20a44aab4c206f12a2bfe05da936051 | ≥ cbc53e08a793b073e79f42ca33f1f3568703540d, < d970341cfa5594614c7a6634886c7688b4f5cafd | ≥ cbc53e08a793b073e79f42ca33f1f3568703540d, < ddc748a391dd8642ba6b2e4fe22e7f2ddf84b7f0 | 4.7
  • linux_kernel≥ 4.7, < 6.12.81 | ≥ 6.13, < 6.18.22 | ≥ 6.19, < 6.19.12 | 7.0:rc1 | 7.0:rc2 | 7.0:rc3 | 7.0:rc4 | 7.0:rc5 | 7.0:rc6
Debian1 product
  • linuxAll versions (No fix recorded) | < 6.12.85-1 | < 6.19.12-1

3 vendors · 159 products

References

23 links
Show all 23 references