CVE-2026-98490: Linux kernel · net: openvswitch: conntrack: fix helper UAF due to extensions realloc
Source GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in e02a83bb0b7a203f6a22f55ad5f426765560f811 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 49% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in e02a83bb0b7a203f6a22f55ad5f426765560f811, afcf362625190c5260530b1d6c7daa98831f6b83, 18866dc1f525f9ee4de7709529d1ae1af8d8e8be +2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 18 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by 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
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix has been implemented in the Linux kernel to ensure that helpers are called only after all extensions are added, preventing the use-after-free condition. Users should apply the official kernel updates that include this fix. No additional mitigation steps are indicated or required beyond applying the patch.
Description
A use-after-free (UAF) vulnerability in the Linux kernel's openvswitch conntrack helper was resolved. The issue involved a raw pointer to the extensions area being stored in an expectations list before all extensions were fully added, leading to potential invalid pointer dereferences when extensions were reallocated. The fix ensures helpers are called only after all extensions are added. The vulnerability does not provide atomicity guarantees and leaves marks and labels set similarly to previous behavior on helper rejection or confirmation failure.
References
- nvd.nist.gov/vuln/detail/CVE-2026-98490 (opens in a new tab)
- git.kernel.org/stable/c/1a4151e6be57b098b7a5ebfbde58585e83200cdc (opens in a new tab)
- git.kernel.org/stable/c/5f23080a625dd7855ab91485c8d691a54a1979f0 (opens in a new tab)
- git.kernel.org/stable/c/afcf362625190c5260530b1d6c7daa98831f6b83 (opens in a new tab)
- git.kernel.org/stable/c/e02a83bb0b7a203f6a22f55ad5f426765560f811 (opens in a new tab)