From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-43131][LOW] drm/amd/pm: Fix null pointer dereference issue [ Upstream Date: Sat, 01 Aug 2026 13:10:42 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-43131 X-AL-KERNEL-Priority: LOW X-AL-KERNEL-Severity: LOW X-AL-KERNEL-Base-Severity: LOW X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 1 X-AL-KERNEL-ActionableScore-Lower: 0 X-AL-KERNEL-Commit: 8e035505fa0e5b7c4306fd3f4e27f8e8f5bfad8c List-Id: CVE: CVE-2026-43131 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: drm/amd/pm: Fix null pointer dereference issue [ Upstream Commit: 8e035505fa0e5b7c4306fd3f4e27f8e8f5bfad8c Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8e035505fa0e5b7c4306fd3f4e27f8e8f5bfad8c Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43131 Analysis date: Sat, 01 Aug 2026 13:10:42 -0400 ActionableScore: 1 ActionableScore lower bound: 0 Actionable bucket: Ordinary Moderate / Low-like Manual review required: NO Summary: A NULL pointer dereference in the AMDGPU SMU RAS message path can crash the kernel when SMU is disabled or uninitialized, but exploitation appears local, configuration dependent, and limited to denial of service. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-43131 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43131 The original announcement does not normally provide a security severity estimate, CVSS assessment, or enough information to determine whether the reported kernel bug represents a practically relevant security issue. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. It combines an autonomous classifier with LLM-assisted technical analysis and a separate ActionableScore mechanism. The purpose of this report is to prioritize Linux kernel CVEs before manual review, identify cases that require prompt investigation, and support automatic closure of issues that are unlikely to have meaningful security impact. Published priority for this report: LOW Manual review required: NO A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-43131 LOW CHECK WITH IMPACT FROM ORIG NN LOW Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-703;CWE-754;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '4.7';DESCR 'A NULL pointer dereference can occur in the AMDGPU SMU RAS message path because amdgpu_smu_ras_send_msg reads adev powerplay pp_handle and then accesses smu ppt_funcs without first checking whether the SMU context exists. If SMU is disabled or not initialized, RAS initialization can dereference a NULL smu pointer and crash the kernel. For the CVSS the PR:L is used in the paranoid score because a local user or delegated service might be able to reach GPU or RAS related control paths in some deployments, while the typical base case requires administrator level control over driver loading or hardware configuration. The issue is not network reachable and there is no direct remote trigger from packet traffic. Impact is denial of service only via kernel crash, with no supported evidence of information disclosure or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) SKIP CVE-2026-43131 SKIP No affected files built, so skip this CVE NO - - unknown MAYBE NULLPTR HARDWARE DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=1 ActionableScoreLower=0 ## 1. ActionableScore * Conservative score: 0 * Paranoid score: 1 * Final recommended bucket: **Ordinary Moderate / Low-like** ## 2. Signal breakdown Conservative signals: * Reliable kernel crash / strong DoS: +1. The patch prevents a NULL pointer dereference of `smu->ppt_funcs` when `adev->powerplay.pp_handle` is NULL. * Requires admin/root/CAP_* in typical deployments: -2. The realistic trigger appears tied to AMDGPU driver initialization, RAS initialization, SMU-disabled configuration, or device management state, which normally requires administrator or boot/module/device control. * Rare AND difficult-to-reach subsystem/configuration: -1. The crash requires SMU to be disabled or not initialized while the RAS path is still reached. Conservative total is below zero, treated as 0. Paranoid adjustment: * Local delegated trigger concern: +1. In some deployments, a local service or reduced-privilege GPU management component might indirectly reach RAS or GPU reset related paths. * Reliable kernel crash / strong DoS: +1. * Rare configuration dependency: -1. Paranoid total: 1. No memory-corruption signal is awarded. This is a NULL pointer dereference only, with no UAF, double-free, OOB write, stale callback, refcount abuse, type confusion, or attacker-controlled overwrite shown by the patch. ## 3. Reachability analysis The likely trigger is local and configuration dependent. It occurs when SMU is disabled or not initialized, but `amdgpu_smu_ras_send_msg()` is still called during RAS initialization. Typical triggering requires control over driver loading, GPU configuration, RAS setup, module parameters, firmware or hardware state, or privileged device-management flows. There is no network reachability. Namespaces or containers do not obviously lower the privilege requirement unless the environment delegates GPU management operations to a less privileged service. The affected path is not a broad default user-facing data plane. Call-site confidence: medium. The changed function and immediate dereference are visible, but broader caller paths are not included in the input. ## 4. Severity interpretation This behaves like a Low-like or ordinary Moderate kernel DoS issue. The theoretical impact is a kernel crash through NULL pointer dereference. There is no realistic evidence of privilege escalation, confidentiality impact, integrity impact, or exploitable memory corruption. The issue should not be treated as an Important candidate based on the provided patch. ## 5. One-sentence report phrase A NULL pointer dereference in the AMDGPU SMU RAS message path can crash the kernel when SMU is disabled or uninitialized, but exploitation appears local, configuration dependent, and limited to denial of service. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED Reason: this is a configuration-dependent NULL pointer dereference with DoS-only impact, no network exposure, no demonstrated memory corruption primitive beyond invalid NULL dereference, and no plausible LPE path shown by the patch. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/amd/pm: Fix null pointer dereference issue [ Upstream Commit: 8e035505fa0e5b7c4306fd3f4e27f8e8f5bfad8c Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8e035505fa0e5b7c4306fd3f4e27f8e8f5bfad8c Changed files: drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c Diff excerpt: Not included in this email. See the upstream URL for the full patch. Full patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8e035505fa0e5b7c4306fd3f4e27f8e8f5bfad8c ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-43131 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43131 The original CVE announcement normally does not include a security-level estimate. In particular, it may not contain a CVSS assessment, an impact level, or enough information to determine whether the reported bug is a practically relevant security issue. One purpose of this parallel CVE list is to provide that missing technical and prioritization information. The original goal of the AL-KERNEL project was to prioritize Linux kernel CVE analysis automatically before manual review. The system can also help identify non-security issues that may be suitable for automatic closure. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. The first analysis stage combines an autonomous classifier with additional LLM-based analysis. The autonomous classifier runs locally on a CPU and is based on a backpropagation neural network. Together, these mechanisms produce a technical vulnerability description, identify likely weakness types, estimate CVSS severity, and provide input for ActionableScore. Two CVSS estimates are retained because incomplete kernel vulnerability information often permits more than one defensible interpretation: Conservative CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 4.7 The conservative vector represents a lower-impact interpretation. The Best/paranoid vector intentionally represents a plausible upper-bound interpretation and should not automatically be treated as demonstrated real-world impact. CVSS may also need to be adjusted for a particular Linux deployment, because actual reachability, privileges, enabled kernel configuration, hardware, namespaces, exposed device nodes, and other environmental conditions can differ significantly between systems. A separate ActionableScore mechanism evaluates practical remediation urgency. Its analysis may include reachability, attack prerequisites, subsystem exposure, memory-corruption characteristics, denial-of-service reliability, and possible confidentiality, integrity, or privilege-escalation impact. Conservative ActionableScore: 0 Paranoid ActionableScore: 1 The final base severity is taken directly from the second tab-separated field of the AL-KERNEL classification result. ActionableScore does not replace or independently override that final AL-KERNEL decision, and if ActionableScore adjusted impact level of ALKERNEL, then you would see self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7. For an AL-KERNEL result of MODERATE, this report uses the following additional presentation split: ActionableScore below 5 -> MODERATE REGULAR ActionableScore 5 or more -> MODERATE 7.0 The distinction between MODERATE REGULAR and MODERATE 7.0 makes it possible to identify Moderate issues that should receive manual analysis and fixes before lower-priority MODERATE REGULAR issues. In many cases, MODERATE REGULAR fixes may wait for a later rebase or routine update. There is one override in which MODERATE REGULAR becomes MODERATE 7.0 even when the ActionableScore is below 5. When the AL-KERNEL result contains the KPANIC flag, a MODERATE result is always presented as MODERATE 7.0. The KPANIC flag selected with few regexps without usage of AI at all, so it helps to detect cases when Kernel Crash happens and similar (to filter False-Negative results from the LLM usage). KPANIC indicates that a reliable kernel crash, kernel panic, or similarly serious kernel availability impact was identified by the classification workflow. AL-KERNEL base severity for this report: LOW KPANIC detected for this report: NO Published priority for this report (same as in Subject): LOW These results are intended to support engineering triage. They are machine-generated estimates, and cases marked for manual review should be validated by a human security engineer before final disposition. For more info read docs linked from here: https://kernelcve.org/ (and you can submit you own patch there to generate such a report for non-existant CVE-id yet). Note that in many cases this AI tool selects higher severity, than real is (means you can expect Importants instead of Moderate 7.0 or Moderates 7.0 instead of regular Moderates). If you see such cases, please use reply email interface to add additional manual analyses info to this particular CVE. And please, please, let me know when you see Lows instead of Importants or Important instead of Low (because particular for such cases I need to tune this AI tool to make it better for this one and next similar). My contact email for such notifications is alexanjelausa@gmail.com (and both send reply to CVE record itself too and see "reply" button below for howto reply).