From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-92504][MODERATE REGULAR] thermal: intel: int3400: clean up ODVP on probe failures [ Upstream Date: Thu, 17 Sep 2026 22:59:29 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-92504 X-AL-KERNEL-Priority: MODERATE REGULAR X-AL-KERNEL-Severity: MODERATE REGULAR X-AL-KERNEL-Base-Severity: MODERATE X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 4 X-AL-KERNEL-ActionableScore-Lower: 3 X-AL-KERNEL-Commit: 5798c714fccf1b4939a98a812b9073da365172c8 List-Id: CVE: CVE-2026-92504 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: thermal: intel: int3400: clean up ODVP on probe failures [ Upstream Commit: 5798c714fccf1b4939a98a812b9073da365172c8 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5798c714fccf1b4939a98a812b9073da365172c8 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-92504 Analysis date: Thu, 17 Sep 2026 22:59:29 -0400 ActionableScore: 4 ActionableScore lower bound: 3 Actionable bucket: Borderline / manual review recommended Manual review required: YES Summary: Intel int3400 ODVP probe failure cleanup could leak sysfs state and may allow repeated freeing of cached ODVP pointers on later unwind paths, but practical triggering appears limited to host-admin-controlled driver or platform management. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-92504 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-92504 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: MODERATE REGULAR Manual review required: YES A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-92504 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-92504 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:L/I:L/A:H';*CWE-401;*CWE-772;CWE-415;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.2';DESCR 'ODVP cleanup in the Intel int3400 thermal driver was incomplete on probe failure paths after evaluate_odvp. If a later probe step failed, per ODVP sysfs files and backing storage could remain allocated after probe unwind, causing a local resource leak and possible driver state inconsistency. The added pointer clearing also indicates that cleanup_odvp can be reached more than once after partial setup failure, so stale cleanup state could create a double cleanup risk in unusual error paths. For the CVSS the PR:H is used for the paranoid score because reliable triggering normally requires administrative control over driver probing, device binding, module handling, fault injection, or similar platform management. The issue is not network reachable. Impact is mainly denial of service or resource leakage, with limited confidentiality and integrity impact kept only for the paranoid score because stale ODVP pointers make manual review reasonable.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 4) YES SIMPLEFIX HARDWARE INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP NO NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=4 ActionableScoreLower=3 PrimitiveClass=CLASS_B RealUAF=YES HostAdminRequired=YES NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES ## 1. ActionableScore * Raw conservative score: 3 * Conservative score: 3 * Raw paranoid score: 4 * Paranoid score: 4 * Final recommended bucket: **Borderline / manual review recommended**:: No floor or cap changed the score. ## 2. Signal breakdown Conservative signals: * +2 Real lifetime violation / double-free candidate: `cleanup_odvp()` frees `priv->odvp_attrs` and `priv->odvp`, and the patch adds pointer clearing because `evaluate_odvp()` can already call cleanup on partial setup failure while probe continues. * +1 Concrete repeated release/free signal: the first `kfree()` can end the allocation lifetime, the exact same cached pointer can remain reachable, and a later `cleanup_odvp()` can perform another `kfree()` on the same pointer. * +1 Concrete resource/reference leak: failures after `evaluate_odvp()` but before the old `free_sysfs` label could leave ODVP sysfs files and backing storage behind. * +1 Plausible kernel DoS: repeated free or inconsistent cleanup can plausibly lead to allocator diagnostics, fault, or resource leakage. * -2 Host-admin-equivalent reachability: reliable triggering appears to require control over platform driver probing, device bind/unbind, module handling, ACPI/platform setup, fault injection, or similar host management. Paranoid additional signal: * +1 Paranoid repeated-free leverage: the second `kfree()` is a write-like allocator lifetime operation through storage whose original object lifetime may already have ended. This is still not treated as controlled reclaim or arbitrary write. Important non-awarded signals: * Controlled reclaim not demonstrated. * Arbitrary write not demonstrated. * Information disclosure not demonstrated. * Privilege escalation not demonstrated. * Remote reachability not established. * Extra availability not awarded beyond the same cleanup failure / crash consequence. * Structured stale-object leverage not awarded separately because the relevant fact is already counted as concrete repeated free. * Weak LPE not separately awarded for the same repeated-free fact. * C/I impact not awarded merely because a double free could theoretically corrupt reused memory. Repeated release/free checklist: * First release can end lifetime: yes, `kfree(priv->odvp_attrs)` and `kfree(priv->odvp)`. * Exact same reference survives first release: yes, old code did not clear cached pointers. * Second operation mutates lifetime/free state: yes, later `cleanup_odvp()` can call `kfree()` again. * +1 Concrete repeated release/free awarded: yes. * Paranoid repeated-free +1 awarded: yes, but only for unresolved allocator lifetime mutation, not for generic heap-reuse speculation. * FLOOR 5 applied: no, because host-admin-equivalent reachability is positively supported and no below-host-admin exploitation path is established. ## 3. Reachability analysis The vulnerable path is in `int3400_thermal_probe()` error unwinding. The trigger requires `evaluate_odvp()` to create ODVP state and then a later probe step, such as `thermal_tripless_zone_device_register()`, to fail. Reliable attacker control is not shown for an ordinary local user. Practical triggering likely requires host-admin-equivalent control over driver probing, device binding or unbinding, module handling, ACPI/platform environment, or fault injection. Namespace-scoped privilege is not relevant. The patch is not network reachable. There is no evidence that a container or user namespace can perform the complete vulnerable operation. Prior host/platform setup is material because this driver depends on Intel ACPI thermal platform state. Special hardware/platform support is involved, but no separate rare-hardware penalty was applied because the host-admin reachability penalty already captures the practical restriction. No race/timing penalty was applied. The issue is an ordered probe failure and unwind sequence, not a demonstrated narrow race. ## 4. Primitive and severity interpretation The exact primitive is incomplete cleanup of ODVP sysfs/state on probe failure plus a directly implied stale cached-pointer cleanup problem. The resource leak is concrete. The pointer clearing strongly indicates that `cleanup_odvp()` can be reached more than once after partial ODVP setup failure, making a repeated free of `priv->odvp_attrs` or `priv->odvp` possible in the old code. This is an active kernel lifetime/ownership bug, but the stale operation is limited to cleanup/probe failure handling. It is not a demonstrated controlled UAF reclaim, attacker-shaped object replacement, callback hijack, arbitrary kernel write, information leak, or privilege-escalation primitive. PrimitiveClass is CLASS_B because a real lifetime violation / double-free candidate is directly implied. It is not CLASS_A because strong exploitation leverage is not established. It is not CLASS_C because the second `kfree()` is more than a shallow stale dereference. ImportantCandidate is NO because the complete trigger appears host-admin-equivalent and no below-host-admin path or strong exploitation primitive is supplied. ManualReview is RECOMMENDED because the patch combines a concrete resource leak with a possible repeated free, and the pointer-nullification change deserves confirmation against full surrounding source. AutoDowngradeAllowed is YES because the issue appears constrained to privileged probe-failure cleanup and lacks meaningful unresolved exploitation leverage for a lower-privileged attacker. Likely operational severity: low to borderline moderate, mainly local privileged DoS / cleanup corruption risk. ## 5. One-sentence report phrase Intel int3400 ODVP probe failure cleanup could leak sysfs state and may allow repeated freeing of cached ODVP pointers on later unwind paths, but practical triggering appears limited to host-admin-controlled driver or platform management. ## 6. Manual review recommendation MANUAL CHECK RECOMMENDED Reason: the patch directly fixes missing cleanup and also clears freed cached pointers, which suggests a possible double-free path, but practical attacker reachability appears host-admin-limited and no strong exploitation primitive is demonstrated. ## 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: thermal: intel: int3400: clean up ODVP on probe failures [ Upstream Commit: 5798c714fccf1b4939a98a812b9073da365172c8 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5798c714fccf1b4939a98a812b9073da365172c8 Changed files: drivers/thermal/intel/int340x_thermal/int3400_thermal.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=5798c714fccf1b4939a98a812b9073da365172c8 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-92504 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-92504 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:L/I:L/A:H The Best / paranoid CVSS score: 5.2 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: 3 Paranoid ActionableScore: 4 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: MODERATE KPANIC detected for this report: NO Published priority for this report (same as in Subject): MODERATE REGULAR 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).