Linux Kernel up to 7.0-rc2 nft_set_pipapo call_rcu denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.63

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 7.0-rc2. This affects the function call_rcu of the component nft_set_pipapo. Such manipulation leads to denial of service. This vulnerability is listed as CVE-2026-23351. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 7.0-rc2. Affected by this issue is the function call_rcu of the component nft_set_pipapo. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_pipapo: split gc into unlink and reclaim phase Yiming Qian reports Use-after-free in the pipapo set type: Under a large number of expired elements, commit-time GC can run for a very long time in a non-preemptible context, triggering soft lockup warnings and RCU stall reports (local denial of service). We must split GC in an unlink and a reclaim phase. We cannot queue elements for freeing until pointers have been swapped. Expired elements are still exposed to both the packet path and userspace dumpers via the live copy of the data structure. call_rcu() does not protect us: dump operations or element lookups starting after call_rcu has fired can still observe the free'd element, unless the commit phase has made enough progress to swap the clone and live pointers before any new reader has picked up the old version. This a similar approach as done recently for the rbtree backend in commit 35f83a75529a ("netfilter: nft_set_rbtree: don't gc elements on insert").

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-23351 since 01/13/2026. The exploitation is known to be easy. There are known technical details, but no exploit is available.

Upgrading to version 6.1.167, 6.6.130, 6.12.77, 6.18.17, 6.19.7 or 7.0-rc3 eliminates this vulnerability. Applying the patch 16f3595c0441d87dfa005c47d8f95be213afaa9e/7864c667aed01a58b87ca518a631322cd0ac34c0/c12d570d71920903a1a0468b7d13b085203d0c93/500a50a301ce962b019ab95053ac70264fec2c21/aff13667708dfa0dce136b8efd81baa9fa6ef261/9df95785d3d8302f7c066050117b04cd3c2048c2 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.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
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: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

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 6.1.167/6.6.130/6.12.77/6.18.17/6.19.7/7.0-rc3
Patch: 16f3595c0441d87dfa005c47d8f95be213afaa9e/7864c667aed01a58b87ca518a631322cd0ac34c0/c12d570d71920903a1a0468b7d13b085203d0c93/500a50a301ce962b019ab95053ac70264fec2c21/aff13667708dfa0dce136b8efd81baa9fa6ef261/9df95785d3d8302f7c066050117b04cd3c2048c2

Timelineinfo

01/13/2026 CVE reserved
03/25/2026 +71 days Advisory disclosed
03/25/2026 +0 days VulDB entry created
03/30/2026 +5 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23351 (🔒)
GCVE (CVE): GCVE-0-2026-23351
GCVE (VulDB): GCVE-100-353108

Entryinfo

Created: 03/25/2026 13:43
Updated: 03/30/2026 10:38
Changes: 03/25/2026 13:43 (59), 03/30/2026 10:38 (1)
Complete: 🔍
Cache ID: 216:16C:103

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