CVE-2026-31516 | Linux Kernel up to 6.12.79/6.18.20/6.19.10 xfrm_hash_rebuild null pointer dereference

VDB-358939 · CVE-2026-31516 · GCVE-0-2026-31516 LINUX KERNEL UP TO 6.12.79/6.18.20/6.19.10 XFRM_HASH_REBUILD NULL POINTER DEREFERENCE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 5.5 $0-$5k 0.25+ Summaryinfo A vulnerability was found in Linux Kernel up to 6.12.79/6.18.20/6.19.10. It has been rated as critical. This impacts the function xfrm_hash_rebuild. This manipulation causes null pointer dereference. The identification of this vulnerability is CVE-2026-31516. There is no exploit available. Upgrading the affected component is advised. Detailsinfo A vulnerability classified as critical was found in Linux Kernel up to 6.12.79/6.18.20/6.19.10. Affected by this vulnerability is the function xfrm_hash_rebuild. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is: In the Linux kernel, the following vulnerability has been resolved: xfrm: prevent policy_hthresh.work from racing with netns teardown A XFRM_MSG_NEWSPDINFO request can queue the per-net work item policy_hthresh.work onto the system workqueue. The queued callback, xfrm_hash_rebuild(), retrieves the enclosing struct net via container_of(). If the net namespace is torn down before that work runs, the associated struct net may already have been freed, and xfrm_hash_rebuild() may then dereference stale memory. xfrm_policy_fini() already flushes policy_hash_work during teardown, but it does not synchronize policy_hthresh.work. Synchronize policy_hthresh.work in xfrm_policy_fini() as well, so the queued work cannot outlive the net namespace teardown and access a freed struct net. It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-31516 since 03/09/2026. Technical details of the vulnerability are known, but there is no available exploit. Upgrading to version 6.12.80, 6.18.21 or 6.19.11 eliminates this vulnerability. Applying the patch 56ea2257b83ee29a543f158159e3d1abc1e3e4fe/8854e9367465d784046362698731c1111e3b39b8/4e2e77843fef473ef47e322d52436d8308582a96/29fe3a61bcdce398ee3955101c39f89c01a8a77e 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. Productinfo Type Operating System Vendor Linux Name Kernel Version 6.12.0 6.12.1 6.12.2 6.12.3 6.12.4 6.12.5 6.12.6 6.12.7 6.12.8 6.12.9 6.12.10 6.12.11 6.12.12 6.12.13 6.12.14 6.12.15 6.12.16 6.12.17 6.12.18 6.12.19 6.12.20 6.12.21 6.12.22 6.12.23 6.12.24 6.12.25 6.12.26 6.12.27 6.12.28 6.12.29 6.12.30 6.12.31 6.12.32 6.12.33 6.12.34 6.12.35 6.12.36 6.12.37 6.12.38 6.12.39 6.12.40 6.12.41 6.12.42 6.12.43 6.12.44 6.12.45 6.12.46 6.12.47 6.12.48 6.12.49 6.12.50 6.12.51 6.12.52 6.12.53 6.12.54 6.12.55 6.12.56 6.12.57 6.12.58 6.12.59 6.12.60 6.12.61 6.12.62 6.12.63 6.12.64 6.12.65 6.12.66 6.12.67 6.12.68 6.12.69 6.12.70 6.12.71 6.12.72 6.12.73 6.12.74 6.12.75 6.12.76 6.12.77 6.12.78 6.12.79 6.18.0 6.18.1 6.18.2 6.18.3 6.18.4 6.18.5 6.18.6 6.18.7 6.18.8 6.18.9 6.18.10 6.18.11 6.18.12 6.18.13 6.18.14 6.18.15 6.18.16 6.18.17 6.18.18 6.18.19 6.18.20 6.19.0 6.19.1 6.19.2 6.19.3 6.19.4 6.19.5 6.19.6 6.19.7 6.19.8 6.19.9 6.19.10 License open-source Website Vendor: https://www.kernel.org/ 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 Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Null pointer dereference CWE: CWE-476 / CWE-404 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Partially Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Kernel 6.12.80/6.18.21/6.19.11 Patch: 56ea2257b83ee29a543f158159e3d1abc1e3e4fe/8854e9367465d784046362698731c1111e3b39b8/4e2e77843fef473ef47e322d52436d8308582a96/29fe3a61bcdce398ee3955101c39f89c01a8a77e Timelineinfo 03/09/2026 CVE reserved 04/22/2026 +43 days Advisory disclosed 04/22/2026 +0 days VulDB entry created 04/22/2026 +0 days VulDB entry last update Sourcesinfo Vendor: kernel.org Advisory: git.kernel.org Status: Confirmed CVE: CVE-2026-31516 (🔒) GCVE (CVE): GCVE-0-2026-31516 GCVE (VulDB): GCVE-100-358939 Entryinfo Created: 04/22/2026 17:23 Changes: 04/22/2026 17:23 (58) Complete: 🔍 Cache ID: 99:A06:101 Discussion No comments yet. 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