CVE-2026-99218: Linux kernel · coredump: hold RCU while releasing parked threads
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.0 High · fixed in fd0fbe84312fda2fc187428c92c50b7d03a9d24c : patch Linux kernel soon.
Data as of 2 Nov 2026, 16:32 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.0 |
|---|
- Patch
- Available – fixed in fd0fbe84312fda2fc187428c92c50b7d03a9d24c, b0eca0edddf4c1dbaf6d1f6a8636b4235f5bc573, a0f09ff4c6b93312e565cfe75d76c3a551a3ec4c +3
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 2 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 2 Nov 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
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Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
This vulnerability has been fixed in multiple Linux kernel commits as listed in the established facts. Users and administrators should apply the official Linux kernel patches that include these fixes to resolve the issue. Since this is a kernel-level flaw, upgrading to a fixed kernel version is the recommended remediation. No alternative mitigations or workarounds are indicated.
Description
CVE-2026-99218 is a high-severity vulnerability in the Linux kernel affecting version 2.6.27. It involves improper handling of parked threads during coredump processing, where the kernel fails to hold an RCU (Read-Copy-Update) reference while releasing parked threads. This can lead to use-after-free conditions when wake_up_process() is called without proper synchronization, potentially causing memory corruption or kernel crashes. The issue has been fixed in several subsequent commits.
References
- git.kernel.org/stable/c/fd0fbe84312fda2fc187428c92c50b7d03a9d24c (opens in a new tab)
- git.kernel.org/stable/c/71146c437bae59e5280f657965dc6d006ee3989b (opens in a new tab)
- git.kernel.org/stable/c/0fce73efee40c65ce26641c5d93942462f9e8307 (opens in a new tab)
- git.kernel.org/stable/c/16e94ed90b1b02398e044d41fd1db34828daa08e (opens in a new tab)
- git.kernel.org/stable/c/a0f09ff4c6b93312e565cfe75d76c3a551a3ec4c (opens in a new tab)
- git.kernel.org/stable/c/b0eca0edddf4c1dbaf6d1f6a8636b4235f5bc573 (opens in a new tab)