CVE-2026-89988: Linux kernel · kprobes: Protect kprobe_blacklist with RCU
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in 630ed8734a02b992e8a97538179c2ece42c5210f : patch Linux kernel soon.
Data as of 30 Oct 2026, 13:04 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
- Patch
- Available – fixed in 630ed8734a02b992e8a97538179c2ece42c5210f, 518d9b5568bb06f86e4434f7a30faa9612ea91ad, 8f406205003f741225f620f0e357ca0de71d45e3 +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 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 30 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
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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
A fix is available and has been applied in the Linux kernel source. The vulnerability is resolved by protecting the kprobe_blacklist with RCU synchronization primitives and safely reclaiming memory after a grace period. Users and administrators should update to a Linux kernel version that includes the fix identified by the listed commit hashes. No additional mitigations are specified beyond applying the official patch.
Description
CVE-2026-89988 is a high-severity vulnerability in the Linux kernel affecting version 3.16. It involves unsafe traversal of the kprobe_blacklist without proper synchronization, leading to potential use-after-free conditions when modules are unloaded. The flaw arises because within_kprobe_blacklist() accesses the blacklist without holding the kprobe_mutex, which can cause dereferencing of freed memory. This function can be called in atomic or non-preemptible contexts where sleeping on kprobe_mutex is not possible. The vulnerability has been addressed by protecting the kprobe_blacklist with Read-Copy-Update (RCU) mechanisms to ensure safe concurrent access and memory reclamation.
References
- git.kernel.org/stable/c/3fb8386682ef4d0858c38bf0d8d8a47ba171fa23 (opens in a new tab)
- git.kernel.org/stable/c/5d97a13defc648c64d138145ace429b6a3d08943 (opens in a new tab)
- git.kernel.org/stable/c/8f406205003f741225f620f0e357ca0de71d45e3 (opens in a new tab)
- git.kernel.org/stable/c/630ed8734a02b992e8a97538179c2ece42c5210f (opens in a new tab)
- git.kernel.org/stable/c/518d9b5568bb06f86e4434f7a30faa9612ea91ad (opens in a new tab)
- git.kernel.org/stable/c/5da247e4d1e8661d4d6f997101d59967e8994e32 (opens in a new tab)
- git.kernel.org/stable/c/6e62cf983a2bd547e6bbd3f935539233e5f97f8f (opens in a new tab)
- git.kernel.org/stable/c/0c4256196b3a105307e2235fbfd85e768bbcdd0f (opens in a new tab)