From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-99196][LOW] net: au1000: move setting of netops to fix crash [ Upstream Date: Wed, 28 Oct 2026 22:18:23 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-99196 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: 0 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: cfc11024fc061bf36044b40de9ecab57ed0a537d List-Id: CVE: CVE-2026-99196 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: net: au1000: move setting of netops to fix crash [ Upstream Commit: cfc11024fc061bf36044b40de9ecab57ed0a537d Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=cfc11024fc061bf36044b40de9ecab57ed0a537d Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-99196 Analysis date: Wed, 28 Oct 2026 22:18:23 -0400 ActionableScore: 0 ActionableScore lower bound: unknown Actionable bucket: Ordinary Moderate Manual review required: NO Summary: AU1000 PHY probing can dereference an uninitialized netdev operations pointer and crash the kernel under `CONFIG_NET_SHAPER`, with no demonstrated non-administrative or memory-corruption path. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-99196 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-99196 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-2026-99196 LOW https://www.kernelcve.org/list/?q=CVE-2026-99196 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=1 LEGACY=LOW RESULT=DIFF TEMP_DISTANCE_MERGE_SKIP=AEGIS_NO_POSITIVE_SEVERITY_EVIDENCE (final Legacy and Aegis differ; FINAL: LOW, Aegis: MODERATE_KPANIC) Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-665;BEST CVSS score: '4.4';DESCR 'The au1000 driver attaches the PHY before initializing dev netdev_ops. With CONFIG_NET_SHAPER enabled, phy_link_topo_add_phy reaches netdev_need_ops_lock and reads the missing operations pointer, causing a NULL pointer dereference during device probe and potentially crashing the kernel. This is a probe time initialization order bug and is not reachable through network traffic. For the CVSS the PR:H value reflects that intentional triggering normally requires administrative control over driver loading, device binding, or system boot. The demonstrated primitive is a NULL pointer dereference with availability impact only and there is no supported UAF, OOB access, information leak, or privilege escalation path. Automated impact decision path. The original SimpleNet classifier selected MODERATE_KPANIC. The primary LLM estimated paranoid CVSS 4.4 and the production ActionableScore returned 0 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were CVSS and initial triage stage MODERATE_KPANIC to MODERATE because the CVSS score, vector or bug class threshold rule was applied. ActionableScore thresholds stage MODERATE to LOW because the ActionableScore threshold rule was applied. final reconciliation stage LOW to LOW because KP specialist did not establish a qualifying panic and the cross model evidence reconciliation rule was applied. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. Exact triggered rule markers were DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS and DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 and KPANIC_UNSUPPORTED_REMOVED and V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED. The independent weaker Aegis shadow evaluated CVSS 2.7 and ActionableScore 1 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE_KPANIC. The models disagreed but the aggregation rules retained the production result. The final reported impact is LOW.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0) MAYBE REMOTE LOCK NULLPTR SIMPLEFIX LEAK NETWORK DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 KPANIC_UNSUPPORTED_REMOVED V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=0 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=YES NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw base score: -3. * Conservative score: 0 after clamping the negative raw score. * Raw paranoid score: -3. * Paranoid score: 0 after clamping. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown * +1 — Reliable kernel crash: with `CONFIG_NET_SHAPER`, PHY attachment reads the still-NULL `dev->netdev_ops`, supporting a probe-time NULL dereference. * -2 — Host-administrator-equivalent trigger: intentional triggering requires control over boot, driver/device binding, or reprobe; no below-admin interface is shown. * -2 — Rare hardware-specific path: the defect requires the AU1000 platform Ethernet device and the affected configuration. * No UAF, OOB access, heap overwrite, stale-object use, authorization bypass, information disclosure, or useful corruption primitive is shown. * No remote point: network packets do not initiate this pre-registration probe sequence. * No additional availability point: it would duplicate the same NULL-dereference crash. 3. Reachability analysis The vulnerable path executes during AU1000 platform-device probing and PHY attachment, before the network device is operational. An attacker cannot reach it through network traffic. Deliberate invocation requires effective host administrative control over boot or device binding. Numeric host UID 0 specifically is not established, and no namespace-scoped capability path or delegated interface is present. Required prerequisites are AU1000 hardware and `CONFIG_NET_SHAPER`; no race is involved. 4. Primitive and severity reading The exact defect is initialization-order failure: active PHY setup consults a mandatory operations pointer before assignment. The resulting behavior is a direct NULL-pointer dereference, classified as CLASS_C crash/DoS rather than memory corruption. The fix merely assigns the static operations table before PHY attachment. There is no attacker-controlled state consumption after corruption, no B5-R retry-accumulated write, no B3 shared-backing write, and no B4 authorization transition. Auto-downgrade is safe because only a hardware/configuration-limited administrative probe-time crash is supported. 5. One-sentence report phrase AU1000 PHY probing can dereference an uninitialized netdev operations pointer and crash the kernel under `CONFIG_NET_SHAPER`, with no demonstrated non-administrative or memory-corruption path. 6. Manual review advice NO MANUAL CHECK NEEDED The patch and call chain establish a constrained probe-time NULL dereference without an unresolved exploit primitive. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: net: au1000: move setting of netops to fix crash [ Upstream Commit: cfc11024fc061bf36044b40de9ecab57ed0a537d Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=cfc11024fc061bf36044b40de9ecab57ed0a537d Changed files: drivers/net/ethernet/amd/au1000_eth.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=cfc11024fc061bf36044b40de9ecab57ed0a537d ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-99196 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-99196 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: Not available The Best / paranoid CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 4.4 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: unknown Paranoid ActionableScore: 0 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).