From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-53316][LOW] drm/amd/ras: Fix NULL deref in ras_core_ras_interrupt_detected() [ Upstream Date: Fri, 26 Jun 2026 16:16:52 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-53316 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: f2f2ed3d359509c311cc6626226e4578d7eb77d8 List-Id: CVE: CVE-2026-53316 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: drm/amd/ras: Fix NULL deref in ras_core_ras_interrupt_detected() [ Upstream Commit: f2f2ed3d359509c311cc6626226e4578d7eb77d8 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f2f2ed3d359509c311cc6626226e4578d7eb77d8 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53316 Analysis date: Fri, 26 Jun 2026 16:16:52 -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 RAS error path can crash the kernel when `ras_core_ras_interrupt_detected()` logs through a missing `ras_core` context, but the issue appears local, device-specific, and DoS-only. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-53316 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53316 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-2026-53316 LOW CHECK 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 RAS error path because ras_core_ras_interrupt_detected may log through ras_core dev after the ras_core pointer is already NULL. This can crash the kernel if the function is reached while the RAS core context is missing or not initialized. For the CVSS the PR:L value in the paranoid score is used because a local user with GPU access might indirectly reach GPU driver recovery or RAS paths in some deployments, although reliable triggering is likely environment dependent. The issue is not network reachable and there is no concrete evidence of UAF, OOB access, information disclosure, or privilege escalation. Impact is denial of service only via kernel crash.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) SKIP CVE-2026-53316 SKIP No affected files built, so skip this CVE NO - - unknown MAYBE NULLPTR SIMPLEFIX ERRORPATH HARDWARE - - 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 * Reliable kernel crash / strong DoS: +1 in paranoid scoring. The patch fixes a direct NULL pointer dereference in an AMDGPU RAS error path, so a kernel crash is possible if the path is reached with `ras_core == NULL`. * Requires admin/root/CAP or privileged device-management conditions in typical deployments: -2 conservative. Reliable triggering likely requires AMDGPU RAS state manipulation, driver recovery paths, fault injection, or hardware/firmware error conditions, not an ordinary unprivileged syscall path. * Rare AND difficult-to-reach subsystem/configuration: -1 conservative. The affected path is AMDGPU RAS-specific and appears to be an error path, not a broad/default kernel interface. * No memory corruption signal: +0. This is a NULL dereference only. The patch does not show UAF, OOB write, stale object reuse, type confusion, refcount misuse, or attacker-controlled overwrite. * No privilege escalation signal: +0. There is no plausible LPE primitive supported by the patch. * No confidentiality or integrity signal: +0. No info leak, writable stale object, or corruption sink is visible. ## 3. Reachability analysis The bug is local/device-path reachable at most. A normal remote attacker cannot trigger it over the network. A local user with access to AMDGPU workloads might indirectly exercise GPU recovery or RAS paths in some deployments, but the specific NULL `ras_core` error path looks environment-dependent and not reliably exposed as an unprivileged interface. Namespaces and containers do not obviously lower the requirement unless GPU device access is delegated into the container. The path is hardware and driver specific. ## 4. Severity interpretation This behaves like a low-end Moderate or Low-like DoS issue. The theoretical impact is a kernel crash from a NULL pointer dereference. Realistic exploitation evidence is weak because the patch only guards an error-path logging dereference and does not expose a memory corruption primitive. It should not be treated as Important-class without additional evidence showing reliable unprivileged triggering or a stronger primitive. ## 5. One-sentence report phrase A NULL pointer dereference in the AMDGPU RAS error path can crash the kernel when `ras_core_ras_interrupt_detected()` logs through a missing `ras_core` context, but the issue appears local, device-specific, and DoS-only. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED This can be auto-closed or handled as non-urgent unless your environment exposes AMDGPU RAS or GPU reset/fault paths to untrusted local users. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/amd/ras: Fix NULL deref in ras_core_ras_interrupt_detected() [ Upstream Commit: f2f2ed3d359509c311cc6626226e4578d7eb77d8 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f2f2ed3d359509c311cc6626226e4578d7eb77d8 Changed files: drivers/gpu/drm/amd/ras/rascore/ras_core.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=f2f2ed3d359509c311cc6626226e4578d7eb77d8 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-53316 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53316 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).