From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-90196][MODERATE REGULAR] ASoC: SOF: validate topology volume range before allocation [ Upstream Date: Thu, 17 Sep 2026 14:09:38 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-90196 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: 3 X-AL-KERNEL-ActionableScore-Lower: 2 X-AL-KERNEL-Commit: 992e130b888699d18da901b593d7a0fb75041a03 List-Id: CVE: CVE-2026-90196 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: ASoC: SOF: validate topology volume range before allocation [ Upstream Commit: 992e130b888699d18da901b593d7a0fb75041a03 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=992e130b888699d18da901b593d7a0fb75041a03 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90196 Analysis date: Thu, 17 Sep 2026 14:09:38 -0400 ActionableScore: 3 ActionableScore lower bound: 2 Actionable bucket: Borderline / manual review recommended Manual review required: YES Summary: ASoC SOF topology parsing accepted invalid volume ranges that could produce unsafe allocation sizes and later out-of-bounds volume table indexing, but reliable triggering normally requires host-admin control of the loaded topology data. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-90196 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90196 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-2026-90196 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-90196 CHECK WITH IMPACT FROM ORIG NN LOW Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H';*CWE-20;CWE-190;CWE-129;*CWE-787;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:H';BEST CVSS score: '6.7';DESCR 'ASoC/SOF volume topology parsing can accept an invalid mixer range where min is greater than max or max is too large for safe signed storage and max plus 1 allocation. The values are used as non-negative indices into a volume table, so a malformed topology can create an unsafe allocation size and later out of bounds table access. For the CVSS the PR:H is used because reliable triggering normally requires control over the SOF topology file or firmware data loaded by the kernel, which is typically restricted to administrators. The issue is not network reachable and is triggered through local device topology loading rather than packet or remote input. Impact is at least local denial of service and in the paranoid case may include confidentiality or integrity impact due to plausible memory corruption from invalid table indexing.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 3) YES SIMPLEFIX HARDWARE INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 NO NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=3 ActionableScoreLower=2 PrimitiveClass=CLASS_B RealUAF=NO HostAdminRequired=YES NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES ## 1. ActionableScore * Raw conservative score: 2 * Conservative score: 2 * Raw paranoid score: 3 * Paranoid score: 3 * Final recommended bucket: **Borderline / manual review recommended**:: No floor or cap changed the score. ## 2. Signal breakdown Conservative signals: * +1 Weak / indirect corruption candidate: malformed topology `min` / `max` can create an invalid volume-table range and unsafe later indexing. * +1 Memory layout invariant restoration: the patch restores consistency between stored range values, `max + 1` allocation size, signed field representation, and later table indexing. * +1 Active persisted invalid state: the invalid range is stored into `scontrol` and can affect later control behavior, not only immediate parsing. * +1 Plausible kernel crash / DoS: invalid allocation size or later out-of-bounds table access can plausibly crash the kernel. * -2 Host-admin-equivalent trigger requirement: reliable triggering normally requires control over SOF topology / firmware data loaded by the kernel, which is normally host-admin controlled. Paranoid additional signal: * +1 Unresolved memory-corruption concern: the patch context supports more than a pure validation-only warning because the values are later used as indices into an allocated kernel table. This does not prove controlled overwrite or LPE, but warrants manual review. Material non-awarded signals: * RealUAF not awarded: no stale lifetime or post-free object use is shown. * CLASS_A not awarded: no controlled reclaim, arbitrary write, callback control, credential corruption, or demonstrated LPE is established. * Confidentiality and integrity bonuses not awarded: OOB table access is plausible, but no concrete disclosure path or unauthorized write target is shown. * Remote reachability not awarded: the vulnerable input is topology data, not network traffic. * Local unprivileged trigger not awarded: ordinary users are not shown to control the loaded SOF topology. * Extra Availability not awarded: no distinct persistent availability impact beyond possible crash is established. * ImportantCandidate not set: the primitive is host-admin-gated and lacks demonstrated below-admin exploitation leverage. ## 3. Reachability analysis The attacker must influence the SOF topology mixer control data loaded by the kernel. In normal deployments, SOF topology files are firmware-like assets located in root-controlled paths and loaded during device initialization or topology setup. That makes the complete reliable trigger host-admin-equivalent based on normal SOF deployment semantics. There is no evidence that an ordinary local user can provide arbitrary topology data to this loader. No namespace-scoped capability path is established. No network path is involved. The issue is hardware/subsystem-specific to SOF audio topology loading, but I did not apply a separate rare-hardware penalty because the key reducing factor is already the privileged topology-control requirement. No race is involved. Triggering depends on malformed topology values such as `min > max` or `max >= INT_MAX`. ## 4. Primitive and severity interpretation The exact primitive is invalid range validation in SOF volume topology parsing. The malformed `min` and `max` values are treated as non-negative volume-table indices, stored in signed fields, used to allocate `max + 1` entries, and later used for table indexing. This is not a UAF and not a repeated release/refcount case. It is an input-validation and integer-range bug with a plausible out-of-bounds access or allocation-size mismatch. The affected state is an active kernel control structure rather than passive metadata, so `PrimitiveClass=CLASS_B` is appropriate. Demonstrated consequence: unsafe topology state that can lead to invalid allocation/indexing and likely local DoS if malformed topology is loaded. Speculative consequence: broader memory corruption impact is plausible enough for manual review, but the patch does not establish a controlled overwrite, arbitrary read/write, or privilege-escalation chain. `ImportantCandidate=NO` because the trigger appears host-admin-controlled and no below-admin or cross-boundary exploitation path is established. `AutoDowngradeAllowed=YES` because the issue does not currently show an unresolved Important-grade primitive reachable below host admin. Likely operational severity: ordinary Moderate / Low-like in most deployments, with manual review recommended due to the memory-corruption-shaped range and allocation issue. ## 5. One-sentence report phrase ASoC SOF topology parsing accepted invalid volume ranges that could produce unsafe allocation sizes and later out-of-bounds volume table indexing, but reliable triggering normally requires host-admin control of the loaded topology data. ## 6. Manual review recommendation MANUAL CHECK RECOMMENDED Reason: the issue is host-admin-gated in normal deployments, but the bug shape involves allocation size, signed range representation, and later table indexing, so it should not be treated as a trivial warning-only fix without review. ## 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: ASoC: SOF: validate topology volume range before allocation [ Upstream Commit: 992e130b888699d18da901b593d7a0fb75041a03 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=992e130b888699d18da901b593d7a0fb75041a03 Changed files: sound/soc/sof/topology.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=992e130b888699d18da901b593d7a0fb75041a03 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-90196 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90196 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:L/PR:H/UI:N/S:U/C:L/I:L/A:H The Best / paranoid CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H The Best / paranoid CVSS score: 6.7 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: 2 Paranoid ActionableScore: 3 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).