CVE-2026-64250: Linux kernel · LoongArch: Report dying CPU to RCU in stop_this_cpu()
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 8 Nov 2026, 16:35 UTC
Rated Medium by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or noneExploitation evidence
Disclosed: evidence found.
CVE published 24 Jul 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 8 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Linux Linux | Affected
| Fixed in– |
AI-suggested
A fix has been implemented in the Linux kernel to call rcutree_report_cpu_dead() during CPU shutdown on LoongArch, which properly informs RCU of offline CPUs and prevents grace period stalls. Users should update to the fixed Linux kernel versions listed in the affectedVersions field or later. No additional mitigation is required beyond applying the official patch.
Description
A Linux kernel vulnerability affecting the LoongArch architecture involves improper reporting of a dying CPU to the Read-Copy Update (RCU) subsystem during CPU shutdown. This flaw can cause the system to hang during reboot or shutdown because RCU waits indefinitely for quiescent states from CPUs that are offline but not properly reported. The issue arises when irq_work_sync() calls synchronize_rcu() after secondary CPUs have been stopped without informing RCU, leading to stalled grace periods and system hangs. The fix involves calling rcutree_report_cpu_dead() to notify RCU of offline CPUs, allowing grace periods to complete and preventing reboot hangs.
References
- git.kernel.org/stable/c/262dadc619e69ebeb97affd334cd1078a9704e98 (opens in a new tab)
- git.kernel.org/stable/c/1fa22de588a65880d6fe54c38c87fffe7d519f60 (opens in a new tab)
- git.kernel.org/stable/c/a0269e928728f970c782319fee53d92d4ea4e512 (opens in a new tab)
- git.kernel.org/stable/c/90e254f18b8c224460082329dd5c42fd30995c2f (opens in a new tab)
- git.kernel.org/stable/c/0833b2b84c2fc1387f8165f0cbf6a02d67f647a5 (opens in a new tab)
- git.kernel.org/stable/c/f2539c56c74691e7a88af6372ba2b48c06ed2fe4 (opens in a new tab)