From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-90239][LOW] media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() [ Upstream Date: Thu, 17 Sep 2026 18:42:50 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-90239 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: 2 X-AL-KERNEL-ActionableScore-Lower: 1 X-AL-KERNEL-Commit: a1f8750668e552837df781783909f2f680958006 List-Id: CVE: CVE-2026-90239 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() [ Upstream Commit: a1f8750668e552837df781783909f2f680958006 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a1f8750668e552837df781783909f2f680958006 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90239 Analysis date: Thu, 17 Sep 2026 18:42:50 -0400 ActionableScore: 2 ActionableScore lower bound: 1 Actionable bucket: Ordinary Moderate Manual review required: NO Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-90239 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90239 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-2026-90239 LOW https://www.kernelcve.org/list/?q=CVE-2026-90239 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:H/UI:N/S:U/C:N/I:N/A:H';*CWE-401;*CWE-772;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.1';DESCR 'AMD ISP4 firmware GPU memory allocation can leak previously allocated pools when a later allocation in the same sequence fails. The issue requires a partial allocation failure and becomes relevant mainly if device initialization or recovery is attempted repeatedly, allowing leaked GPU or system memory resources to accumulate. For the CVSS the PR:H value is used because reliable triggering normally requires administrative control over driver loading, device initialization, reset, or recovery. The issue is not network reachable. No UAF, OOB access, invalid free, information disclosure, or write primitive is visible in the affected path. Impact is limited to resource exhaustion and denial of service, with high availability impact considered only for sustained repeated failures.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2) SKIP CVE-2026-90239 UNKNOWN SKIP The Fixes patch not applied yet, so unlikely that actual: url YES NO NO unknown MAYBE SIMPLEFIX LEAK ERRORPATH HARDWARE - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=2 ActionableScoreLower=1 PrimitiveClass=NONE RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES 1. ActionableScore * Raw conservative score: 1 * Conservative score: 1 * Raw paranoid score: 2 * Paranoid score: 2 * No floor or cap was applied. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown Conservative signals: * +1 Concrete persistent kernel resource leak. Successfully allocated GPU memory pools are lost when a later allocation fails, because the original error path returns without releasing them. Paranoid additional signal: * +1 Meaningful accumulation and resource exhaustion. Repeated initialization or recovery failures can leak additional GPU or system memory pools and may eventually impair the ISP device or system availability. Negative signals: * No negative privilege penalty was applied because host-admin-equivalent privilege is plausible but not positively established by the supplied call path. * No hardware rarity penalty was applied. The code is hardware-specific, but the evidence does not establish rare or physical-only hardware. * No timing penalty was applied because this is an ordered allocation error path, not a race. Important non-awarded signals: * No UAF, double release, OOB access, invalid free, or stale-object use is established. * No attacker-controlled overwrite, controlled reclaim, or arbitrary read or write is demonstrated. * No reliable kernel crash or host-wide immediate DoS is established. * No confidentiality or integrity impact is supported. * No remote reachability or namespace-scoped trigger is established. * The paranoid resource-exhaustion point does not change the bug into a memory-corruption primitive. 3. Reachability analysis The vulnerable path runs when ISP4 firmware GPU memory pools are allocated and one allocation fails after earlier allocations succeeded. Repeated triggering would likely require repeated device initialization, driver probing, reset, or recovery together with appropriately timed memory-allocation failures. The supplied diff does not show the callers or the complete user-facing control path. Administrative device control may be required, but that requirement is not positively established, so HostAdminRequired is UNKNOWN rather than YES. There is no evidence that an ordinary user can invoke the complete sequence or that any relevant operation is available through an attacker-created namespace. NamespaceScopedPrivilege is therefore UNKNOWN. AMD ISP4-capable hardware and the affected driver are prerequisites. The issue is not network reachable, and no race or special timing window is involved beyond obtaining a partial allocation failure. 4. Primitive and severity interpretation The exact defect is a persistent resource leak on a partial-allocation error path. Earlier GPU memory pool allocations remain allocated when a later allocation returns an error. This is not a lifetime violation involving post-free access. There is no first release followed by a second release, no dangling reference, and no active structured stale object. PrimitiveClass is NONE and RealUAF is NO. The demonstrated consequence is leaked GPU or associated system memory. The practical worst case is cumulative resource exhaustion after repeated failures. Host-wide failure, memory corruption, privilege escalation, and security-boundary bypass remain unsupported. ImportantCandidate is NO because the patch establishes only a resource leak without corruption, isolation bypass, or a low-privilege exhaustion path. AutoDowngradeAllowed is YES because no unresolved Important-grade primitive would be discarded. 5. One-sentence report phrase A partial AMD ISP4 firmware GPU memory allocation failure leaks pools allocated earlier in the sequence, potentially causing cumulative resource exhaustion after repeated initialization failures. 6. Manual review recommendation NO MANUAL CHECK NEEDED The issue is a concrete but constrained resource leak with no evidence of UAF, memory corruption, authorization bypass, remote exposure, or privilege escalation. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() [ Upstream Commit: a1f8750668e552837df781783909f2f680958006 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a1f8750668e552837df781783909f2f680958006 Changed files: drivers/media/platform/amd/isp4/isp4_interface.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=a1f8750668e552837df781783909f2f680958006 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-90239 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90239 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:L The Best / paranoid CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 4.1 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: 1 Paranoid ActionableScore: 2 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).