CVE-2026-89547
Last modified
CVE-2026-89547 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Check svc pool percpu counter allocation __svc_create() initializes three per-pool percpu_counter stats and ignores every return value. On SMP, percpu_counter_init() fails when __alloc_percpu_gfp() cannot satisfy the allocation, leaving the failed counter with fbc->counters == NULL and its embedded raw_spinlock_t, list_head, and count never initialized. EPSS estimates a 0.57% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Check svc pool percpu counter allocation __svc_create() initializes three per-pool percpu_counter stats and ignores every return value. On SMP, percpu_counter_init() fails when __alloc_percpu_gfp() cannot satisfy the allocation, leaving the failed counter with fbc->counters == NULL and its embedded raw_spinlock_t, list_head, and count never initialized. __svc_create() returns the half-constructed svc_serv to nfsd, lockd, or the NFS callback service anyway. Once that service is live, the hot-path increments in svc_xprt_enqueue(), svc_handle_xprt(), and svc_pool_wake_idle_thread() reach a counter whose backing pointer is NULL. The pointer is a per-cpu offset, so the access does not fault: it resolves to offset zero of the current CPU's per-cpu area and silently corrupts whatever variable lives there. A /proc/fs/nfsd/pool_stats read walks the same NULL per-cpu storage and returns garbage, and on CONFIG_DEBUG_SPINLOCK or lockdep it splats on the never-initialized lock. Creating the broken service requires a percpu allocation failure during RPC server startup, so it is reachable only by a local administrator under memory pressure or fault injection; a remote peer cannot induce the bad state on its own. Check each percpu_counter_init() return value in __svc_create() and fail when an allocation fails, unwinding the counters already set up in the current pool and in every pool initialized before it. A discrete percpu_counter_destroy() per counter at teardown frees each per-cpu allocation exactly once.
Metrics
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= ccf08bed6e7a80519569456edd2ea21b7b1701c6, < 57ac7d899409b0a9b768cf417e3bb86bcca3d4c6; >= ccf08bed6e7a80519569456edd2ea21b7b1701c6, < 3a2b7649de76376a69f1d3ed2a539fb15907cd4d; >= ccf08bed6e7a80519569456edd2ea21b7b1701c6, < bd1ef2cfb44d72b7aa6943e87b206eb0e30fbd0c; >= ccf08bed6e7a80519569456edd2ea21b7b1701c6, < b541a15046976e481618726cc23db0fb22d576db; >= ccf08bed6e7a80519569456edd2ea21b7b1701c6, < 43e11e164704dde975c9edb370de1a06bec67270 |
| Linux | Linux | 6.3 |
References
Timeline
- Published
- Last Modified
- Status
- Received
Frequently Asked Questions
What is CVE-2026-89547?
How severe is CVE-2026-89547?
How do I fix CVE-2026-89547?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-89541In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89542In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89543In the Linux kernel, the following vulnerability has been re…
- CVE-2026-89544In the Linux kernel, the following vulnerability has been re…7.5
- CVE-2026-89545In the Linux kernel, the following vulnerability has been re…7.8
- CVE-2026-89546In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89548In the Linux kernel, the following vulnerability has been re…7.8
- CVE-2026-89549In the Linux kernel, the following vulnerability has been re…7.5
- CVE-2026-8955Privilege escalation in the DOM: Workers component. This vul…8.8
- CVE-2026-89550In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89551In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89552In the Linux kernel, the following vulnerability has been re…
Are you affected by CVE-2026-89547?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
