Linux Kernel up to 7.0-rc4 cache_release file descriptor consumption

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 7.0-rc4. Affected is the function cache_release. Performing a manipulation results in file descriptor consumption. This vulnerability is reported as CVE-2026-31400. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 7.0-rc4. This affects the function cache_release. The manipulation with an unknown input leads to a file descriptor consumption vulnerability. CWE is classifying the issue as CWE-769. This entry has been deprecated because it was a duplicate of CWE-774. All content has been transferred to CWE-774. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: sunrpc: fix cache_request leak in cache_release When a reader's file descriptor is closed while in the middle of reading a cache_request (rp->offset != 0), cache_release() decrements the request's readers count but never checks whether it should free the request. In cache_read(), when readers drops to 0 and CACHE_PENDING is clear, the cache_request is removed from the queue and freed along with its buffer and cache_head reference. cache_release() lacks this cleanup. The only other path that frees requests with readers == 0 is cache_dequeue(), but it runs only when CACHE_PENDING transitions from set to clear. If that transition already happened while readers was still non-zero, cache_dequeue() will have skipped the request, and no subsequent call will clean it up. Add the same cleanup logic from cache_read() to cache_release(): after decrementing readers, check if it reached 0 with CACHE_PENDING clear, and if so, dequeue and free the cache_request.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-31400 since 03/09/2026. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 313522 (Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2026-1681)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.167, 6.6.130, 6.12.78, 6.18.20, 6.19.10 or 7.0-rc5 eliminates this vulnerability. Applying the patch 7bcd5e318876ac638c8ceade7a648e76ac8c48e1/41f6ba6c98a618043d2cd71030bf9a752dfab8b2/301670dcd098c1fe5c2fe90fb3c7a8f4814d2351/be5c35960e5ead70862736161836e2d1bc7352dc/373457de14281c1fc7cace6fc4c8a267fc176673/17ad31b3a43b72aec3a3d83605891e1397d0d065 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (313522) and EUVD (EUVD-2026-18782). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: File descriptor consumption
CWE: CWE-769 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 313522
Nessus Name: Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2026-1681)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.167/6.6.130/6.12.78/6.18.20/6.19.10/7.0-rc5
Patch: 7bcd5e318876ac638c8ceade7a648e76ac8c48e1/41f6ba6c98a618043d2cd71030bf9a752dfab8b2/301670dcd098c1fe5c2fe90fb3c7a8f4814d2351/be5c35960e5ead70862736161836e2d1bc7352dc/373457de14281c1fc7cace6fc4c8a267fc176673/17ad31b3a43b72aec3a3d83605891e1397d0d065

Timelineinfo

03/09/2026 CVE reserved
04/03/2026 +24 days Advisory disclosed
04/03/2026 +0 days VulDB entry created
05/20/2026 +47 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-31400 (🔒)
GCVE (CVE): GCVE-0-2026-31400
GCVE (VulDB): GCVE-100-355167
EUVD: 🔒

Entryinfo

Created: 04/03/2026 18:17
Updated: 05/20/2026 21:28
Changes: 04/03/2026 18:17 (58), 04/19/2026 17:46 (1), 05/10/2026 01:13 (2), 05/20/2026 21:28 (10)
Complete: 🔍
Cache ID: 216::103

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