From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98280][MODERATE REGULAR] drm/xe/i2c: Disable IRQ on unbind [ Upstream Date: Sat, 10 Oct 2026 17:44:21 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98280 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: 0 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: 571ccbc801aa4d22a22d9f924b826c77052330f0 List-Id: CVE: CVE-2026-98280 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: drm/xe/i2c: Disable IRQ on unbind [ Upstream Commit: 571ccbc801aa4d22a22d9f924b826c77052330f0 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=571ccbc801aa4d22a22d9f924b826c77052330f0 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98280 Analysis date: Sat, 10 Oct 2026 17:44:21 -0400 ActionableScore: 0 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-2026-98280 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98280 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: NO A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-98280 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-98280 CHECK WITH IMPACT FROM ORIG NN MODERATE | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=0 LEGACY=MODERATE RESULT=DIFF (independent Legacy and Aegis differ; FINAL: MODERATE, Aegis: MODERATE_KPANIC) Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H';*CWE-416;CWE-362;CWE-667;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H';BEST CVSS score: '6.4';DESCR 'A race in the drm xe I2C unbind path can allow an SGUnit I2C interrupt to access struct xe_i2c after the object has been freed. The vulnerable window is small because the interrupt must occur after resource teardown has started but before the IRQ source is disabled. This creates a use after free in IRQ context and can cause an Oops or kernel crash. Reuse of the freed allocation could potentially produce wider memory corruption impact, although the available code does not establish a controlled write or a reliable privilege escalation primitive. For the CVSS the PR:H reflects that reliable triggering normally requires administrative control of driver unbind or device removal. AC:H reflects the IRQ timing race. The issue is local and is not directly reachable through network traffic. Impact is at least a local denial of service and in the worst defensible case may affect confidentiality and integrity due to use after free memory access.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0) MAYBE USB UAF HARDWARE DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=0 PrimitiveClass=CLASS_B RealUAF=YES HostAdminRequired=YES NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw conservative score: 0 * Conservative score: 0 * Raw paranoid score: 0 * Paranoid score: 0 * No floor or cap was applied. The real UAF floors do not apply because host-admin-equivalent control of the unbind path is established. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown Positive signals: * +2 Real UAF or active lifetime violation. The commit directly states that `struct xe_i2c` can be freed while the SGUnit I2C IRQ remains enabled, permitting post-lifetime access from the interrupt handler. * +1 Realistic kernel crash. An IRQ-context dereference of the freed object can plausibly cause an Oops or host crash. Negative signals: * -2 Host-admin-equivalent privilege. Deliberately unbinding or unloading the driver for the host-owned physical GPU is a host device-management operation. Ordinary render-node access, DRM master status, or compositor privileges do not establish access to this operation. * -1 Narrow and externally difficult timing. The commit explicitly describes a small window during one-time teardown, and the IRQ must arrive after the object lifetime ends but before the interrupt source is disabled. Important non-awarded signals: * No controlled reclaim, attacker-shaped replacement object, arbitrary write, disclosure, callback control, or privilege escalation is established. * Structured stale-object leverage is not awarded. Although `struct xe_i2c` is structured, the supplied context only establishes an asynchronous teardown-time IRQ access. * Attacker-influenced lifetime manipulation is not awarded. No below-host-admin actor is shown to control both unbind and IRQ timing. * No extra Availability point is awarded because it would double-count the same possible kernel crash. * No C or I signal is awarded merely because heap reuse is theoretically possible. * No remote or firmware-mediated reachability bonus is supported. * No hardware rarity penalty is applied. Intel Xe GPU dependency is hardware-specific but not proven rare. * B5-R does not apply because no retry-accumulated heap OOB write exists. * B3-PENDING does not apply because no shared-backing write exists. * B4-PENDING does not apply because there is no authorization decision bypass. Repeated release and refcount checks: * No first release followed by a second release of the exact reference is shown. * No concrete second lifetime or refcount mutation exists. * Concrete repeated release or refcount +1 was not awarded. * Paranoid repeated-refcount leverage was withheld. * FLOOR 5 was not applied. Arithmetic: * Conservative: +2 UAF, +1 crash, -2 host administration, -1 narrow teardown race = 0. * Paranoid: the same established mechanics apply. Generic heap reuse cannot supply an additional point. 3. Reachability analysis The vulnerable state occurs while the Xe I2C component is being removed during driver unbind. Intentional unbind, module removal, or equivalent lifecycle control over a host-owned GPU is a host-administration operation. An ordinary logged-in user with render-node access is not shown to control unbind. DRM master, a compositor, or a delegated display service is also not shown to possess complete device-lifecycle control. No DRM ioctl or render operation that independently initiates the vulnerable teardown is supplied. The operation is not user-namespace or device-namespace scoped. The physical GPU and its driver lifecycle remain host resources. No prior setup beyond a present Intel Xe device and loaded driver is relevant, but those conditions do not provide an attacker trigger. The race is narrow. An SGUnit I2C interrupt must occur during the interval between object destruction and IRQ disablement. Repeated privileged bind and unbind attempts may increase the chance, but no ordinary attacker-controlled source for precise IRQ generation is established. 4. Primitive and severity interpretation The exact primitive is an asynchronous post-lifetime dereference of `struct xe_i2c` by the SGUnit I2C interrupt path. It is therefore a real Class B UAF involving an active structured object, not merely a NULL dereference or passive bookkeeping error. The stale use is constrained to device teardown and the supplied evidence does not show that reclaimed fields are consumed through callbacks, attacker-controlled pointers, offsets, refcounts, or another exploitation-relevant operation. There is also no repeated release or second refcount mutation. The demonstrated practical consequence is a possible kernel Oops or crash. Wider memory corruption is theoretically possible after allocator reuse, but no mechanism for controlled reclaim, replacement contents, directed read or write, or privilege escalation is established. `ImportantCandidate=NO` because the available evidence describes a host-admin-triggered, narrow teardown UAF without meaningful unresolved exploitation leverage beyond the stale IRQ dereference. `AutoDowngradeAllowed=YES` because this matches the constrained Class B cleanup or asynchronous teardown category. Manual review remains recommended to confirm the IRQ handler operations and actual object-free ordering. 5. One-sentence report phrase A narrow host-admin-triggered race during Xe I2C driver unbind can let an SGUnit interrupt access a freed xe_i2c object and crash the kernel, but no controlled reclaim or exploitation primitive beyond the teardown-time UAF is established. 6. Manual review recommendation MANUAL CHECK RECOMMENDED Confirm the precise free ordering and fields consumed by the IRQ handler, but the supplied evidence does not justify mandatory Important-preserving review. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/xe/i2c: Disable IRQ on unbind [ Upstream Commit: 571ccbc801aa4d22a22d9f924b826c77052330f0 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=571ccbc801aa4d22a22d9f924b826c77052330f0 Changed files: drivers/gpu/drm/xe/xe_i2c.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=571ccbc801aa4d22a22d9f924b826c77052330f0 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98280 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98280 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:L/I:L/A:H The Best / paranoid CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H The Best / paranoid CVSS score: 6.4 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: 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).