CVE-2026-31639
CVE-2026-31639 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (2nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-25532
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix key reference count leak from call->key When creating a client call in rxrpc_alloc_client_call(), the code obtains a reference to the key. This is never cleaned up and gets leaked when the call is destroyed. Fix this by freeing call->key in rxrpc_destroy_call(). Before the patch, it shows the key reference counter elevated: $ cat /proc/keys | grep afs@54321 1bffe9cd I--Q--i 8053480 4169w 3b010000 1000 1000 rxrpc afs@54321: ka $ After the patch, the invalidated key is removed when the code exits: $ cat /proc/keys | grep afs@54321 $
Frequently asked questions
- What is CVE-2026-31639?
- In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix key reference count leak from call->key When creating a client call in rxrpc_alloc_client_call(), the code obtains a reference to the key. This is never cleaned up and gets leaked when the call is destroyed. Fix this by freeing call->key in rxrpc_destroy_call(). Before the patch, it shows the key reference counter elevated: $ cat /proc/keys | grep afs@54321 1bffe9cd I--Q--i 8053480 4169w 3b010000 1000 1000 rxrpc afs@54321: ka $ After the patch, the invalidated key is removed when the code exits: $ cat /proc/keys | grep afs@54321 $
- How severe is CVE-2026-31639?
- CVE-2026-31639 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2026-31639 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-31639?
- CVE-2026-31639 primarily affects Linux Linux Kernel. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-31639?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-31639 have an EU (EUVD) identifier?
- Yes. CVE-2026-31639 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25532.
- When was CVE-2026-31639 published?
- CVE-2026-31639 was published on 2026-04-24 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/2e6ef713b1598f6acd7f302fa6b12b6731c89914
- https://git.kernel.org/stable/c/978108902ee4ef2b348ff7ec36ad014dc5bc6dc6
- https://git.kernel.org/stable/c/d666540d217e8d420544ebdfbadeedd623562733
- https://git.kernel.org/stable/c/e6b7943c5dc875647499da09bf4d50a8557ab0c3
- https://git.kernel.org/stable/c/f1a7a3ab0f35f83cf11bba906b9e948cf3788c28
Affected products (9)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.2:-:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*
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