Critical severity · published Aug 15, 2026
CVE-2026-72220
sunrpc: harden rq_procinfo lifecycle to prevent double-free
9.8
CVSS
0.6%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
sunrpc: harden rq_procinfo lifecycle to prevent double-free
The svc_release_rqst() function executes the callback inside
rqstp->rq_procinfo->pc_release. However, if a worker thread begins
processing a new request and encounters an early error path (e.g.,
unsupported protocol, short frame, or bad auth) before a valid
rq_procinfo is installed, a stale release hook can be re-triggered
against reused state from the previous RPC, resulting in a double-free
or use-after-free vulnerability.
Harden the lifecycle of rq_procinfo by:
1. Ensuring svc_release_rqst() always clears rq_procinfo after the
optional pc_release() call, regardless of whether the hook exists.
2. Explicitly clearing rq_procinfo at request entry in svc_process()
before any early decode or drop paths.
3. Ensuring svc_process_bc() does the same at backchannel entry.
This guarantees that error flows will not encounter a non-NULL stale
rq_procinfo pointer when there is nothing to release.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 50% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
d9adbb6e10bf7d4223d3d521ede1b2052903bc5e before 66014ab165cb01bfef5836939412a8ef98d5d5ff; d9adbb6e10bf7d4223d3d521ede1b2052903bc5e before 31ba490c02d476a5e4f90b8845932ac9db8aa71b; d9adbb6e10bf7d4223d3d521ede1b2052903bc5e before 18d216788bef06332ff8901670ecf1ed8f6eb614; 6.18 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-72220
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-72220
git.kernel.org
https://git.kernel.org/stable/c/18d216788bef06332ff8901670ecf1ed8f6eb614
git.kernel.org
https://git.kernel.org/stable/c/31ba490c02d476a5e4f90b8845932ac9db8aa71b
git.kernel.org
https://git.kernel.org/stable/c/66014ab165cb01bfef5836939412a8ef98d5d5ff
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