CVE-2026-98530: Linux kernel · kprobes: Fix permanent hang when flushing the kprobe optimizer
Affects Linux kernelSource CVE Database V5
Not known to be exploited : upgrade to f05a01fc7d4f731b4c100d2aef1e85ad77728862 or 5bfa9f1a9dcb6ecb607adbc1c0226605c972935b soon.
Data as of 26 Oct 2026, 17:16 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in f05a01fc7d4f731b4c100d2aef1e85ad77728862, 5bfa9f1a9dcb6ecb607adbc1c0226605c972935b
Exploitation 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 Linux kernel to f05a01fc7d4f731b4c100d2aef1e85ad77728862 or 5bfa9f1a9dcb6ecb607adbc1c0226605c972935b.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available in the Linux kernel as identified by the fixed commit hashes f05a01fc7d4f731b4c100d2aef1e85ad77728862 and 5bfa9f1a9dcb6ecb607adbc1c0226605c972935b. Users and administrators should update to a kernel version including these fixes to resolve the permanent hang issue when flushing the kprobe optimizer.
Description
A vulnerability in the Linux kernel kprobes subsystem causes a permanent hang when flushing the kprobe optimizer via the sysctl interface. Writing 0 to /proc/sys/debug/kprobes-optimization while a kprobe is jump-optimized results in a process sleeping indefinitely in an uninterruptible state with a mutex held, causing subsequent sysctl operations to hang. The issue arises from improper synchronization and completion handling in the optimizer flushing logic. The flaw has been fixed by replacing the completion mechanism with a counter and proper wake-up signaling to allow multiple flushers to wait correctly without deadlock.