From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-93158][LOW] crypto: sa2ul - stop probe if context pool creation fails [ Upstream Date: Fri, 18 Sep 2026 08:12:37 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-93158 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: 304dcd26bfc3ce6771c2bd3b7c0299dcfd5f4e06 List-Id: CVE: CVE-2026-93158 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: crypto: sa2ul - stop probe if context pool creation fails [ Upstream Commit: 304dcd26bfc3ce6771c2bd3b7c0299dcfd5f4e06 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=304dcd26bfc3ce6771c2bd3b7c0299dcfd5f4e06 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93158 Analysis date: Fri, 18 Sep 2026 08:12:37 -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-2026-93158 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93158 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-2026-93158 LOW https://www.kernelcve.org/list/?q=CVE-2026-93158 CHECK WITH IMPACT FROM ORIG NN MODERATE 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-252;CWE-754;**CWE-476;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '4.7';DESCR 'sa2ul probe ignored failure from sa_init_mem(), so the driver could continue initialization without the DMA pool used for security context buffers. Later crypto request setup depends on that pool and may hit an invalid driver state or a NULL pointer dereference, causing a local denial of service. For the CVSS the PR:L is used in the paranoid score because an unprivileged local process might be able to submit crypto requests after a failed probe state exists, but reliable creation of that state usually needs driver probe control or memory pressure. The issue is not network reachable. Impact is denial of service only, with no supported confidentiality or integrity impact from the patch context.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2) YES INIT SIMPLEFIX DMAorINTERRUPT LINUS MEMORY DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=2 ActionableScoreLower=1 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES 1. ActionableScore * Raw conservative score: 1 * Conservative score: 1 * Raw paranoid score: 2 * Paranoid score: 2 * Final recommended bucket: **Ordinary Moderate**:: No floor or cap was applied. 2. Signal breakdown Conservative signals: * +1: Invalid driver initialization state can lead to later NULL pointer dereference or request failure because sa_init_mem() failure leaves the security context DMA pool unavailable while probe continues. * 0: No RealUAF. No stale post-lifetime object use is established. * 0: No concrete repeated release/refcount operation is established. * 0: No controlled reclaim, arbitrary write, OOB access, callback control, or privilege escalation primitive is established. * 0: No confidentiality or integrity impact is supported. * 0: No remote reachability is established. * 0: No extra availability point. The same possible crash is already counted once. Paranoid additional signal: * +1: The failed state may be externally exercised later because probe can continue into DMA setup, crypto algorithm registration, and child population, making later crypto request setup a plausible trigger for the invalid state. Negative signals: * No -2 host-admin penalty was applied because host-admin-equivalent privilege is not positively established for every possible later request path. * No namespace-scoped privilege bonus was applied because namespace reachability is not relevant or established. * No rare-hardware penalty was applied. The issue is hardware-specific, but the prompt requires more than generic driver specificity for a reducing signal. 3. Reachability analysis The vulnerable condition starts during sa_ul_probe() when sa_init_mem() fails to create the DMA pool for security context buffers. Creating or reliably forcing that failed probe state likely depends on platform-driver probing, device presence, and allocation failure or memory pressure, but the supplied evidence does not positively establish host-admin-equivalent privilege as required for the complete trigger. After probe incorrectly continues, later request setup depends on the missing pool. Those later requests may come from normal crypto API consumers after algorithms are registered, but the supplied context does not prove ordinary unprivileged reachability for the complete sequence. Therefore HostAdminRequired is UNKNOWN rather than YES or NO. There is no network trigger. There is no namespace-scoped capability path. The bug is not a race. Special sa2ul-capable hardware or platform configuration is required in practice, but this is not scored as a strong negative because the patch itself is a driver fix and hardware specificity alone is not enough. 4. Primitive and severity interpretation The exact primitive is unchecked error handling during driver probe. The driver may publish or continue using a partially initialized state where dev_data->sc_pool was never created. This is not an active-object UAF and not fixed stale storage. It is best classified as CLASS_C invalid-state or NULL-dereference behavior. The demonstrated consequence is local denial of service through request failure or kernel crash. The speculative consequence would be broader misuse of the partially initialized crypto driver state, but no concrete memory corruption, repeated refcount mutation, arbitrary write, information leak, or privilege escalation path is established. ImportantCandidate is NO because the patch supports DoS-only invalid-state behavior without a meaningful unresolved corruption primitive. AutoDowngradeAllowed is YES because no Class A or strong Class B primitive remains unresolved. 5. One-sentence report phrase sa2ul probe ignored failure from sa_init_mem(), allowing the driver to continue without the security context DMA pool and later causing crypto request setup to hit an invalid state or NULL pointer dereference, resulting in local denial of service only. 6. Manual review recommendation NO MANUAL CHECK NEEDED Reason: this is an unchecked initialization failure with possible NULL dereference or request-path DoS, but no UAF, no repeated lifetime mutation, no controlled corruption, no remote trigger, and no supported privilege-escalation path. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: crypto: sa2ul - stop probe if context pool creation fails [ Upstream Commit: 304dcd26bfc3ce6771c2bd3b7c0299dcfd5f4e06 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=304dcd26bfc3ce6771c2bd3b7c0299dcfd5f4e06 Changed files: drivers/crypto/sa2ul.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=304dcd26bfc3ce6771c2bd3b7c0299dcfd5f4e06 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-93158 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93158 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: 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).