CVE-2026-98490: Linux kernel · net: openvswitch: conntrack: fix helper UAF due to extensions realloc
Affects Linux kernelSource CVE Database V5
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 is available and has been applied in the Linux kernel in the commits identified by hashes e02a83bb0b7a203f6a22f55ad5f426765560f811, afcf362625190c5260530b1d6c7daa98831f6b83, 18866dc1f525f9ee4de7709529d1ae1af8d8e8be, 5f23080a625dd7855ab91485c8d691a54a1979f0, and 1a4151e6be57b098b7a5ebfbde58585e83200cdc. Users and administrators should update affected Linux kernel versions to these fixed versions or later to remediate this vulnerability.
Description
CVE-2026-98490 is a critical use-after-free vulnerability in the Linux kernel's Open vSwitch conntrack helper subsystem. It occurs due to a raw pointer to the extensions area being retained in an expectations list while the extension space is reallocated, leading to invalid pointer dereference. The flaw is fixed by ensuring helpers are called only after all extensions are added. The vulnerability has a CVSS score of 9.8 and affects Linux kernel version 4.3.
References
- git.kernel.org/stable/c/18866dc1f525f9ee4de7709529d1ae1af8d8e8be (opens in a new tab)
- git.kernel.org/stable/c/afcf362625190c5260530b1d6c7daa98831f6b83 (opens in a new tab)
- git.kernel.org/stable/c/5f23080a625dd7855ab91485c8d691a54a1979f0 (opens in a new tab)
- git.kernel.org/stable/c/e02a83bb0b7a203f6a22f55ad5f426765560f811 (opens in a new tab)
- git.kernel.org/stable/c/1a4151e6be57b098b7a5ebfbde58585e83200cdc (opens in a new tab)