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VulnerabilityPublished

CVE-2026-98442: Linux kernel · net/sched: act_ct: fix helper UAF due to extensions realloc

Source GCVE Database

0
Authoritative record:CVE-2026-98442· High 7.8

Not known to be exploited · CVSS 7.8 High · fixed in dad19b59da050cb60d3f7023dac2a042a84bf0bd : patch Linux kernel soon.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score
7.8High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in dad19b59da050cb60d3f7023dac2a042a84bf0bd, 8988f4d11f3fba0ab38122178836c683ad516a05, 1679bbf5fbeac52a310b1a58b2b301bbf388bdbf +2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 18 Oct 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ a21b06e7319129994f339ed47f512bbe57b77f5b, < dad19b59da050cb60d3f7023dac2a042a84bf0bd
Fixed in
  • dad19b59da050cb60d3f7023dac2a042a84bf0bd
LinuxLinuxAffected
  • ≥ a21b06e7319129994f339ed47f512bbe57b77f5b, < 8988f4d11f3fba0ab38122178836c683ad516a05
Fixed in
  • 8988f4d11f3fba0ab38122178836c683ad516a05
LinuxLinuxAffected
  • ≥ a21b06e7319129994f339ed47f512bbe57b77f5b, < 1679bbf5fbeac52a310b1a58b2b301bbf388bdbf
Fixed in
  • 1679bbf5fbeac52a310b1a58b2b301bbf388bdbf
LinuxLinuxAffected
  • ≥ a21b06e7319129994f339ed47f512bbe57b77f5b, < 812c16a255e7773a544e88b39ae6daed25544d30
Fixed in
  • 812c16a255e7773a544e88b39ae6daed25544d30
LinuxLinuxAffected
  • ≥ a21b06e7319129994f339ed47f512bbe57b77f5b, < 31f5fe29a572037ee19c233dfe506849940c484b
Fixed in
  • 31f5fe29a572037ee19c233dfe506849940c484b
LinuxLinuxAffected
  • =6.2
Fixed in–

AI-suggested

A fix has been implemented in the Linux kernel to address this use-after-free vulnerability by ensuring helpers are called only after all extensions are added. Users should apply the official kernel update containing this fix when available. No additional mitigation steps are indicated.

Description

A use-after-free (UAF) vulnerability in the Linux kernel's net/sched act_ct helper was resolved. The issue involved a raw pointer to the extensions area being stored in an expectations list, which could become invalid if extensions were reallocated before the helper was called. This could lead to accessing freed memory during expectation removal. The fix ensures helpers are called only after all extensions are added. The helper rejection behavior regarding marks and labels remains consistent with previous handling, and no atomicity guarantees are provided by the API.

References

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