CVE-2026-23405 | Linux Kernel up to 6.6.129/6.12.76/6.18.17/6.19.7/7.0-rc3 apparmor privilege escalation

VDB-354619 · CVE-2026-23405 · GCVE-0-2026-23405 LINUX KERNEL UP TO 6.6.129/6.12.76/6.18.17/6.19.7/7.0-RC3 APPARMOR PRIVILEGE ESCALATION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 4.4 $0-$5k 2.00+ Summaryinfo A vulnerability classified as critical has been found in Linux Kernel up to 6.6.129/6.12.76/6.18.17/6.19.7/7.0-rc3. Affected by this issue is some unknown functionality of the component apparmor. This manipulation causes an unknown weakness. The identification of this vulnerability is CVE-2026-23405. There is no exploit available. It is recommended to upgrade the affected component. Detailsinfo A vulnerability classified as critical was found in Linux Kernel up to 6.6.129/6.12.76/6.18.17/6.19.7/7.0-rc3. Affected by this vulnerability is some unknown processing of the component apparmor. The impact remains unknown. The summary by CVE is: In the Linux kernel, the following vulnerability has been resolved: apparmor: fix: limit the number of levels of policy namespaces Currently the number of policy namespaces is not bounded relying on the user namespace limit. However policy namespaces aren't strictly tied to user namespaces and it is possible to create them and nest them arbitrarily deep which can be used to exhaust system resource. Hard cap policy namespaces to the same depth as user namespaces. It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-23405 since 01/13/2026. The exploitation appears to be difficult. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/01/2026). Upgrading to version 6.6.130, 6.12.77, 6.18.18, 6.19.8 or 7.0-rc4 eliminates this vulnerability. Applying the patch 3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e/853ce31ca72097d23991a06876a2ccb5cb64b603/d42b2b6bb77ca40ee34ab74ad79305840b5f315d/7b6495ead2c611647f6b11441a852324e3eb8616/306039414932c80f8420695a24d4fe10c84ccfb2 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 6.6.129 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 6.18.0 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 6.19.0 6.19.1 6.19.2 6.19.3 6.19.4 6.19.5 6.19.6 6.19.7 7.0-rc1 7.0-rc2 7.0-rc3 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: Privilege escalation CWE: Unknown 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 6.6.130/6.12.77/6.18.18/6.19.8/7.0-rc4 Patch: 3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e/853ce31ca72097d23991a06876a2ccb5cb64b603/d42b2b6bb77ca40ee34ab74ad79305840b5f315d/7b6495ead2c611647f6b11441a852324e3eb8616/306039414932c80f8420695a24d4fe10c84ccfb2 Timelineinfo 01/13/2026 CVE reserved 04/01/2026 +77 days Advisory disclosed 04/01/2026 +0 days VulDB entry created 04/01/2026 +0 days VulDB entry last update Sourcesinfo Vendor: kernel.org Advisory: git.kernel.org Status: Confirmed CVE: CVE-2026-23405 (🔒) GCVE (CVE): GCVE-0-2026-23405 GCVE (VulDB): GCVE-100-354619 Entryinfo Created: 04/01/2026 11:25 Changes: 04/01/2026 11:25 (57) Complete: 🔍 Cache ID: 99:5E9:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸