# CVE-2026-89545

## Summary

- **CVE ID:** CVE-2026-89545
- **Severity:** HIGH
- **CVSS Score:** 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** N/A
- **Published:** Sep 11, 2026
- **Last Modified:** Sep 13, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:

sunrpc: defer rq_argp and rq_resp free until after RCU grace period

svc_rqst_free() frees rqstp->rq_argp and rqstp->rq_resp synchronously
via kfree(), but defers the rqstp struct free via kfree_rcu().  After
svc_exit_thread() calls list_del_rcu() and svc_rqst_free(), there is
a window where RCU readers that started before list_del_rcu() can still
traverse the thread list and find the rqstp.  These readers (e.g.
nfsd_nl_rpc_status_get_dumpit()) dereference rqstp->rq_argp, which has
already been freed — a use-after-free.

Fix this by moving the kfree of rq_argp and rq_resp into an explicit
call_rcu() callback alongside the struct free.  Resources not accessed
by RCU readers (bvec, buffer pages, scratch folio, auth_data) remain
synchronously freed.

## Affected Products

- Linux — Linux (812443865c5fc255363d4a684a62c086af1addca)
- Linux — Linux (3.19)
- Linux — Linux (0)
- Linux — Linux (6.18.50)
- Linux — Linux (7.2.4)
- Linux — Linux (7.3-rc1)

## References

- [CNA](https://git.kernel.org/stable/c/08bc49e0541260bf294962cf889a32a2d2713ad6)
- [CNA](https://git.kernel.org/stable/c/e0c5693d3f9a5d4911735ab0e0eba4eecb1f1090)
- [CNA](https://git.kernel.org/stable/c/c479bde671cbe2f9e152834a8b0eb7c3c295bbaf)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.16%
- **EPSS Percentile:** 5.3

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._