From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-64488][LOW] ALSA: aoa: check snd_ctl_new1() return value [ Upstream Date: Sat, 25 Jul 2026 08:30:39 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-64488 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: b0154ebc6dc552c389a574b1e221d728e10346e7 List-Id: CVE: CVE-2026-64488 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: ALSA: aoa: check snd_ctl_new1() return value [ Upstream Commit: b0154ebc6dc552c389a574b1e221d728e10346e7 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b0154ebc6dc552c389a574b1e221d728e10346e7 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64488 Analysis date: Sat, 25 Jul 2026 08:30:39 -0400 ActionableScore: 1 ActionableScore lower bound: 0 Actionable bucket: Ordinary Moderate / Low-like Manual review required: NO Summary: ALSA AOA may dereference a NULL snd_kcontrol pointer after an allocation failure in snd_ctl_new1() during codec attach, causing a local crash-only DoS on rare affected hardware. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-64488 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64488 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-2026-64488 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-252;CWE-703;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '4.7';DESCR 'ALSA aoa can dereference a NULL snd_kcontrol pointer because snd_ctl_new1() may fail during allocation and layout_attached_codec can still access ctl.id.name or pass ctl to aoa_snd_ctl_add. The trigger depends on an out-of-memory condition during AOA codec attach or driver probe, so reliable exploitation is difficult and tied to local system state rather than remote input. For the CVSS the PR:L is used for the paranoid score because a local user may be able to contribute to memory pressure while the driver attach path is reached by system activity, although the base case is closer to PR:H when module loading or reprobe control is required. The issue is not network reachable. Impact is denial of service via kernel crash only, with no supported path to information disclosure or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) SKIP CVE-2026-64488 UNKNOWN SKIP No affected files built, so skip this CVE NO - - unknown MAYBE NULLPTR SIMPLEFIX HARDWARE LINUS 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 Triggered signals: * Reliable kernel crash / strong DoS: +1 `snd_ctl_new1()` may return NULL and the old code can dereference `ctl->id.name` or pass NULL to `aoa_snd_ctl_add()`, causing a NULL pointer dereference. Negative / limiting signals: * Requires admin/root or privileged device reprobe in typical deployments: -2 Reliable triggering normally requires driver probe, reprobe, module/device control, or a controlled low-memory condition during AOA codec attach. * Rare hardware / non-broad exposure: -1 or -2 ALSA AOA is a niche Apple Onboard Audio path and not a broad default server/workstation attack surface. * Hard or unreliable condition: -1 The failure requires allocation failure at a narrow point during codec attachment. Not awarded: * No generic memory corruption bonus. This is a NULL dereference, not UAF, OOB write, double free, or type confusion. * No privilege escalation plausibility. No reclaim, overwrite, callback control, refcount abuse, or object replacement is shown. * No confidentiality or integrity impact. The primitive is crash-only. * No network reachability. ## 3. Reachability analysis The bug is reachable only when the AOA audio driver attaches a codec and `snd_ctl_new1()` fails due to memory allocation failure. A normal local unprivileged user does not directly invoke this path reliably. A paranoid interpretation gives limited credit to local memory-pressure influence, but the attach/probe condition is still not under ordinary unprivileged control. Containers and namespaces do not meaningfully improve reachability unless they also allow device/module management, which is not typical. The subsystem is hardware-specific and uncommon. ## 4. Severity interpretation This behaves like ordinary Moderate or Low-like kernel DoS, not Important. The theoretical failure mode is a kernel NULL pointer dereference and crash. There is no evidence of practical memory corruption, privilege escalation, information disclosure, or cross-boundary security bypass. ## 5. One-sentence report phrase ALSA AOA may dereference a NULL snd_kcontrol pointer after an allocation failure in snd_ctl_new1() during codec attach, causing a local crash-only DoS on rare affected hardware. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED This can be auto-closed or handled in deferred routine patching because it is a rare hardware-specific NULL dereference with crash-only impact and no supported LPE or memory-corruption primitive. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: ALSA: aoa: check snd_ctl_new1() return value [ Upstream Commit: b0154ebc6dc552c389a574b1e221d728e10346e7 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b0154ebc6dc552c389a574b1e221d728e10346e7 Changed files: sound/aoa/fabrics/layout.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=b0154ebc6dc552c389a574b1e221d728e10346e7 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-64488 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64488 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).