Linux Kernel up to 6.18.39/7.1.4 sunrpc svc_release_rqst use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k0.50-

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.39/7.1.4. It has been declared as very critical. This affects the function svc_release_rqst of the component sunrpc. Executing a manipulation can lead to use after free. The identification of this vulnerability is CVE-2026-72220. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.39/7.1.4. It has been declared as very critical. This vulnerability affects the function svc_release_rqst of the component sunrpc. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-72220 since 08/09/2026. The exploitation appears to be easy. The attack can be initiated remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 08/15/2026).

Upgrading to version 6.18.40, 7.1.5 or 7.2-rc1 eliminates this vulnerability. Applying the patch 66014ab165cb01bfef5836939412a8ef98d5d5ff/31ba490c02d476a5e4f90b8845932ac9db8aa71b/18d216788bef06332ff8901670ecf1ed8f6eb614 is able to eliminate this problem.

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Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.40/7.1.5/7.2-rc1
Patch: 66014ab165cb01bfef5836939412a8ef98d5d5ff/31ba490c02d476a5e4f90b8845932ac9db8aa71b/18d216788bef06332ff8901670ecf1ed8f6eb614

Timelineinfo

08/09/2026 CVE reserved
08/15/2026 +6 days Advisory disclosed
08/15/2026 +0 days VulDB entry created
08/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-72220 (🔒)
GCVE (CVE): GCVE-0-2026-72220
GCVE (VulDB): GCVE-100-390634

Entryinfo

Created: 08/15/2026 13:31
Changes: 08/15/2026 13:31 (59)
Complete: 🔍
Cache ID: 216::103

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