7.3

CVE-2026-43025: netfilter: ctnetlink: ignore explicit helper on new expectations

Modified
AliasesUBUNTU-CVE-2026-43025DEBIAN-CVE-2026-43025
Published 01-05-2026Last modified 19-10-2026

Vulnerability summary

CVE-2026-43025 is a high (CVSS 7.3) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.4% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.3, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.3/10
010
High · v3.1 (CVE.org)
EPSS score
0.13%
0%100%
Low · -0.04 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 144 · Related 142
MGASA-2026-0108MGASA-2026-0110SUSE-SU-2026:21834-1SUSE-SU-2026:2195-1SUSE-SU-2026:2238-1SUSE-SU-2026:22598-1

Showing 100 of 144.

Timeline

  1. 01-05-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: ignore explicit helper on new expectations Use the existing master conntrack helper, anything else is not really supported and it just makes validation more complicated, so just ignore what helper userspace suggests for this expectation. This was uncovered when validating CTA_EXPECT_CLASS via different helper provided by userspace than the existing master conntrack helper: BUG: KASAN: slab-out-of-bounds in nf_ct_expect_related_report+0x2479/0x27c0 Read of size 4 at addr ffff8880043fe408 by task poc/102 Call Trace: nf_ct_expect_related_report+0x2479/0x27c0 ctnetlink_create_expect+0x22b/0x3b0 ctnetlink_new_expect+0x4bd/0x5c0 nfnetlink_rcv_msg+0x67a/0x950 netlink_rcv_skb+0x120/0x350 Allowing to read kernel memory bytes off the expectation boundary. CTA_EXPECT_HELP_NAME is still used to offer the helper name to userspace via netlink dump.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.13%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

Decrease -0.04 pp

From 0.17% 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) | < 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≥ bd0779370588386e4a67ba5d0b176cfded8e6a53, < e135f8e8212cbed12a03ab8dec77fa1247139897 | ≥ bd0779370588386e4a67ba5d0b176cfded8e6a53, < 2ea0f35f235f70c133ad61fe05ba013753b978c6 | ≥ bd0779370588386e4a67ba5d0b176cfded8e6a53, < 0f6c33697ccfac6499d0b7a4dbdec5d3a3a566cd | ≥ bd0779370588386e4a67ba5d0b176cfded8e6a53, < 187b6ec5229ea93cb04c4f6d3b52efc80f513d0d | ≥ bd0779370588386e4a67ba5d0b176cfded8e6a53, < 21a04c31db4057deec85fcd6cc63d720b38819c3 | ≥ bd0779370588386e4a67ba5d0b176cfded8e6a53, < 917b61fa2042f11e2af4c428e43f08199586633a | 3.12
  • linux_kernel≥ 3.12, < 6.1.168 | ≥ 6.2, < 6.6.134 | ≥ 6.7, < 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
  • linux< 6.1.170-1 | < 6.12.85-1 | < 6.19.12-1

3 vendors · 160 products

References

27 links
Show all 27 references