CVE-2026-31406 | Linux Kernel up to 6.12.79/6.18.20/6.19.10/7.0-rc5 xfrm_nat_keepalive_net_fini state issue (EUVD-2026-19198)

VDB-355498 · CVE-2026-31406 · EUVD-2026-19198 LINUX KERNEL UP TO 6.12.79/6.18.20/6.19.10/7.0-RC5 XFRM_NAT_KEEPALIVE_NET_FINI STATE ISSUE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 4.4 $0-$5k 1.62 Summaryinfo A vulnerability labeled as critical has been found in Linux Kernel up to 6.12.79/6.18.20/6.19.10/7.0-rc5. Affected by this vulnerability is the function xfrm_nat_keepalive_net_fini. Executing a manipulation can lead to state issue. This vulnerability appears as CVE-2026-31406. There is no available exploit. The affected component should be upgraded. Detailsinfo A vulnerability was found in Linux Kernel up to 6.12.79/6.18.20/6.19.10/7.0-rc5. It has been declared as critical. This vulnerability affects the function xfrm_nat_keepalive_net_fini. The manipulation with an unknown input leads to a state issue vulnerability. The CWE definition for the vulnerability is CWE-371. The impact remains unknown. CVE summarizes: In the Linux kernel, the following vulnerability has been resolved: xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini() After cancel_delayed_work_sync() is called from xfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining states via __xfrm_state_delete(), which calls xfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work. The following is a simple race scenario: cpu0 cpu1 cleanup_net() [Round 1] ops_undo_list() xfrm_net_exit() xfrm_nat_keepalive_net_fini() cancel_delayed_work_sync(nat_keepalive_work); xfrm_state_fini() xfrm_state_flush() xfrm_state_delete(x) __xfrm_state_delete(x) xfrm_nat_keepalive_state_updated(x) schedule_delayed_work(nat_keepalive_work); rcu_barrier(); net_complete_free(); net_passive_dec(net); llist_add(&net->defer_free_list, &defer_free_list); cleanup_net() [Round 2] rcu_barrier(); net_complete_free() kmem_cache_free(net_cachep, net); nat_keepalive_work() // on freed net To prevent this, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync(). The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-31406 since 03/09/2026. The exploitation appears to be difficult. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 04/06/2026). Upgrading to version 6.12.80, 6.18.21, 6.19.11 or 7.0-rc6 eliminates this vulnerability. Applying the patch 32d0f44c2f14d60fe8e920e69a28c11051543ec1/2255ed6adbc3100d2c4a83abd9d0396d04b87792/21f2fc49ca6faa393c31da33b8a4e6c41fc84c13/daf8e3b253aa760ff9e96c7768a464bc1d6b3c90 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 vulnerability database at EUVD (EUVD-2026-19198). 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 7.0-rc1 7.0-rc2 7.0-rc3 7.0-rc4 7.0-rc5 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: 4.6 VulDB Meta Temp Score: 4.4 VulDB Base Score: 4.6 VulDB Temp Score: 4.4 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: State issue CWE: CWE-371 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 6.12.80/6.18.21/6.19.11/7.0-rc6 Patch: 32d0f44c2f14d60fe8e920e69a28c11051543ec1/2255ed6adbc3100d2c4a83abd9d0396d04b87792/21f2fc49ca6faa393c31da33b8a4e6c41fc84c13/daf8e3b253aa760ff9e96c7768a464bc1d6b3c90 Timelineinfo 03/09/2026 CVE reserved 04/06/2026 +27 days Advisory disclosed 04/06/2026 +0 days VulDB entry created 04/06/2026 +0 days VulDB entry last update Sourcesinfo Vendor: kernel.org Advisory: git.kernel.org Status: Confirmed CVE: CVE-2026-31406 (🔒) GCVE (CVE): GCVE-0-2026-31406 GCVE (VulDB): GCVE-100-355498 EUVD: 🔒 Entryinfo Created: 04/06/2026 10:21 Updated: 04/06/2026 12:30 Changes: 04/06/2026 10:21 (58), 04/06/2026 12:30 (1) Complete: 🔍 Cache ID: 99:FB0:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸