From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-89851][LOW] scsi: qla2xxx: Fix FCE trace enable parsing in debugfs Date: Wed, 16 Sep 2026 14:45:19 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-89851 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: unknown X-AL-KERNEL-Commit: b0c08c08a08b6cca0e7e192bcbe0514e41fcc55f List-Id: CVE: CVE-2026-89851 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: scsi: qla2xxx: Fix FCE trace enable parsing in debugfs Commit: b0c08c08a08b6cca0e7e192bcbe0514e41fcc55f Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b0c08c08a08b6cca0e7e192bcbe0514e41fcc55f Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-89851 Analysis date: Wed, 16 Sep 2026 14:45:19 -0400 ActionableScore: 1 ActionableScore lower bound: unknown 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-2026-89851 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-89851 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-2026-89851 LOW https://www.kernelcve.org/list/?q=CVE-2026-89851 CHECK WITH IMPACT FROM ORIG NN MODERATE Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-252;CWE-703;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.5';DESCR 'A NULL-pointer dereference in the qla2xxx debugfs FCE trace control path occurs because qla2x00_dfs_fce_write can call kstrtoul with a NULL result pointer. A local user who can write to the affected debugfs file can trigger the bug with a valid numeric input, causing a kernel oops or panic and denial of service. For the CVSS the PR:L is used for the paranoid score because some deployments may delegate driver diagnostics or debugfs access to a reduced capability local account rather than full host administration. In typical systems the practical privilege requirement is higher because debugfs and SCSI driver debug controls are normally administrator only. The issue is not network reachable and does not show a UAF, OOB write, information leak, or direct privilege escalation primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1) YES WRITE OOB DANGER INIT SIMPLEFIX HARDWARE DEBUGFS LINUS 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=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: 1 * Paranoid score: 1 * Final recommended bucket: **Ordinary Moderate**:: No floor or cap was applied. 2. Signal breakdown Positive signals: * +1 Reliable kernel crash / strong DoS. The commit directly states that successful parsing through kstrtoul() with a NULL result pointer can dereference NULL and oops. Negative or non-awarded signals: * +0 Weak corruption concern. This is an invalid NULL pointer dereference with no useful post-corruption primitive shown. * +0 Real UAF not awarded. No stale object, use-after-free, double release, refcount misuse, or lifetime violation is established. * +0 Concrete repeated release/refcount not awarded. There is no first release, surviving dangling reference, or second lifetime mutation. * +0 Controlled reclaim not demonstrated. * +0 Arbitrary or directed kernel write not demonstrated. * +0 Confidentiality and integrity not awarded. No information disclosure, protected object access, or unauthorized state modification is shown. * +0 Remote reachability not established. The trigger is a local debugfs write path. * +0 Extra availability not awarded. The same oops/crash is already counted once. * No privilege penalty was applied because host-admin-equivalent access is plausible for debugfs but not fully proven from the supplied file mode/context. 3. Reachability analysis The vulnerable operation is writing to the qla2xxx FCE trace control file in debugfs. A caller that can write a valid numeric string to this debugfs file can reach qla2x00_dfs_fce_write(), causing kstrtoul(buf, 0, NULL) to attempt storing the parsed value through a NULL result pointer. This is local only. It is not packet-triggered and has no direct network attack surface. In typical deployments, debugfs and low-level SCSI driver diagnostic controls are restricted to administrators, but the supplied patch does not show the debugfs file mode or complete permission path. Therefore HostAdminRequired is UNKNOWN rather than YES. The operation is not meaningfully namespace-scoped. Prior setup likely requires the qla2xxx driver and corresponding debugfs node to exist. This is driver-specific, but no additional score penalty is applied solely because it is a driver path. No race is involved. The trigger is a deterministic parse path. 4. Primitive and severity interpretation The exact primitive is a NULL pointer dereference caused by passing a NULL result pointer to kstrtoul(). The old code also assigned the integer return code from kstrtoul() into an unsigned long enable variable, inverting intended enable/disable behavior on parse success versus parse failure. This is not active structured stale-object use. It is not fixed stale storage. It is not cleanup-only UAF. It is not repeated lifetime/refcount corruption. The demonstrated consequence is kernel oops or panic, i.e. local denial of service. PrimitiveClass=CLASS_C because the behavior is crash/DoS from invalid pointer use without an independently useful corruption, ownership, authorization, or lifetime primitive. ImportantCandidate=NO because no exploitation leverage beyond crash is established. AutoDowngradeAllowed=YES because automatic downgrade would not discard an unresolved kernel corruption or security-boundary primitive. Likely operational severity is ordinary Moderate or Low-like depending on local debugfs exposure. 5. One-sentence report phrase A local debugfs write to the qla2xxx FCE trace control path can trigger a NULL pointer dereference in qla2x00_dfs_fce_write(), causing a kernel oops or panic without evidence of UAF, information disclosure, or privilege escalation. 6. Manual review recommendation NO MANUAL CHECK NEEDED Reason: this is a deterministic local debugfs NULL dereference DoS with no UAF, refcount mutation, controlled corruption, boundary bypass, or network reachability shown. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: scsi: qla2xxx: Fix FCE trace enable parsing in debugfs Commit: b0c08c08a08b6cca0e7e192bcbe0514e41fcc55f Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b0c08c08a08b6cca0e7e192bcbe0514e41fcc55f Commit description: qla2x00_dfs_fce_write() called kstrtoul() with a NULL result pointer, so a successful parse would dereference NULL and oops. Worse, the int return value (0 on success, negative errno on failure) was assigned to the unsigned long enable flag, inverting the intended logic: a valid number was treated as "disable" while a parse failure enabled FCE. Parse the value into enable and propagate parse errors to userspace. Fixes: 841df27 ("scsi: qla2xxx: Move FCE Trace buffer allocation to user control") Cc: stable@vger.kernel.org Reported-by: Sashiko Signed-off-by: Nilesh Javali Link: https://patch.msgid.link/20260730155838.2119230-10-njavali@marvell.com Signed-off-by: Martin K. Petersen (Oracle) Signed-off-by: Greg Kroah-Hartman Changed files: drivers/scsi/qla2xxx/qla_dfs.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=b0c08c08a08b6cca0e7e192bcbe0514e41fcc55f ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-89851 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-89851 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:N/I:N/A:H The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 5.5 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: 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).