From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-97915][MODERATE REGULAR] accel/ivpu: Limit firmware log name prints to field size Date: Fri, 25 Sep 2026 10:35:39 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-97915 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: 3 X-AL-KERNEL-ActionableScore-Lower: 2 X-AL-KERNEL-Commit: 6dbba89df4e842d226f5cd3dbc5e94533cfceea2 List-Id: CVE: CVE-2026-97915 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: accel/ivpu: Limit firmware log name prints to field size Commit: 6dbba89df4e842d226f5cd3dbc5e94533cfceea2 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6dbba89df4e842d226f5cd3dbc5e94533cfceea2 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97915 Analysis date: Fri, 25 Sep 2026 10:35:39 -0400 ActionableScore: 3 ActionableScore lower bound: 2 Actionable bucket: Borderline / manual review recommended Manual review required: YES Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-97915 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97915 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: YES A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-97915 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-97915 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:L/I:N/A:L';CWE-125;CWE-170;*CWE-200;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N';BEST CVSS score: '3.6';DESCR 'An information disclosure can occur in the IVPU firmware log path because the firmware supplied name is a fixed size character array that is not guaranteed to contain a terminating NUL byte. Printing this field with an unbounded string conversion can read beyond the name and expose adjacent bytes from the shared tracing BO through dmesg or the debugfs firmware log output. For the CVSS the PR:L value is used in the paranoid score because a local user with delegated NPU access may be able to exercise the firmware logging path, although access to dmesg and debugfs is commonly restricted and must be confirmed for the affected deployment. The issue is not network reachable. The demonstrated impact is limited confidentiality loss from an out of bounds read. A low availability impact is also considered in the paranoid case if the scan reaches an inaccessible mapping boundary. There is no write primitive and no supported path to privilege escalation.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 3) SKIP CVE-2026-97915 UNKNOWN SKIP The Fixes patch not applied yet, so unlikely that actual: url YES NO NO unknown MAYBE SIMPLEFIX LOG DEBUGFS DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_GUESSCVSS INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=3 ActionableScoreLower=2 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES 1. ActionableScore * Raw conservative score: 2 * Conservative score: 2 * Raw paranoid score: 3 * Paranoid score: 3 * No floor or cap was applied. * Final recommended bucket: **Borderline / manual review recommended**:: 2. Signal breakdown Conservative signals: * +1 Firmware-mediated external influence. The NPU firmware populates the fixed-size name field and can supply it without a terminating NUL byte. * +1 Confidentiality plausible. The commit explicitly establishes that adjacent bytes from the shared tracing BO can be emitted through dmesg or debugfs. * Total: 2. Additional paranoid signal: * +1 Potential kernel fault. An unbounded string scan could continue to an inaccessible mapping boundary and fault, although no crash is demonstrated by the supplied evidence. * Total: 3. Not awarded: * No strong corruption point. The primitive is a read beyond a fixed-size field, not an overwrite. * No remote-reachability point. Input is mediated by local NPU firmware rather than directly supplied over a network. * No local-unprivileged point. Ordinary-user control of the firmware field and access to the resulting output are not established. * No strong or weak LPE point. There is no write, reclaim, callback, credential, or authorization primitive. * No additional availability point. The possible mapping-boundary fault is already the entire paranoid availability signal. * No hardware penalty. The patch requires IVPU/NPU hardware, but the supplied evidence does not establish that it is rare or physical-attacker-only. * No privilege penalty. Host-admin-equivalent privilege is not positively established. * No UAF, repeated release, refcount mutation, or lifetime violation exists. 3. Reachability analysis The malformed field originates from NPU firmware in a shared tracing BO. The evidence does not establish that an ordinary local process can directly choose the name bytes or force the missing terminator. Exposure also depends on reaching the firmware-log parsing path and reading dmesg or the IVPU debugfs output. Access to dmesg and debugfs is commonly restricted, but the exact product permissions are not supplied. Therefore host-admin privilege cannot be marked either required or unnecessary. No user-namespace or namespace-scoped capability path is shown. No direct network trigger exists. IVPU hardware and firmware tracing are prerequisites. The patch shows no race. Trigger repeatability depends on whether firmware repeatedly produces an unterminated name. 4. Primitive and severity interpretation The exact primitive is a sequential out-of-bounds read caused by passing a firmware-populated, potentially unterminated fixed-size character array to unbounded string formatting. The read bytes are exposed through kernel logging or debugfs, establishing a limited disclosure path. This is fixed shared-buffer storage, not an active structured-object UAF. There is no release, stale reference, repeated refcount mutation, write primitive, controlled target, or privilege-escalation mechanism. The demonstrated consequence is disclosure of adjacent tracing-BO bytes. A kernel fault from scanning beyond the mapped BO is a defensible paranoid possibility, but it is not demonstrated. The issue is CLASS_C because the primitive is constrained to an uncontrolled sequential read with limited disclosure and no stronger corruption or boundary-bypass mechanism. ImportantCandidate is NO because neither substantial disclosure nor a strong corruption primitive is established. AutoDowngradeAllowed is YES because no unresolved lifetime, ownership, write, or authorization primitive remains. Operational severity is Low-like to borderline Moderate, subject to deployment-specific log permissions and firmware influence. 5. One-sentence report phrase An unterminated firmware supplied IVPU log name can make the kernel read beyond its fixed size field and expose adjacent tracing buffer bytes through dmesg or debugfs, with a possible mapping boundary fault but no demonstrated write or privilege escalation primitive. 6. Manual review recommendation MANUAL CHECK RECOMMENDED Confirm whether an unprivileged NPU client can influence firmware tracing names and whether such a client can read the affected dmesg or debugfs output. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: accel/ivpu: Limit firmware log name prints to field size Commit: 6dbba89df4e842d226f5cd3dbc5e94533cfceea2 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6dbba89df4e842d226f5cd3dbc5e94533cfceea2 Commit description: The name in struct vpu_tracing_buffer_header is a fixed-size array populated by the NPU firmware. It is expected to be NUL-terminated, but nothing on the host side enforces this, so printing it with an unbounded string conversion would read past the field if the terminator is ever missing and expose adjacent bytes of the shared tracing BO through dmesg and the debugfs FW log output. Print at most as many characters as the name field holds, so the output never runs past it even if the string is not NUL-terminated. Cc: stable@vger.kernel.org Reported-by: sashiko-bot Closes: https://sashiko.dev/#/patchset/20260827102339.281799-1-dawid.osuchowski@linux.intel.com?part=2 Fixes: d4e4257 ("accel/ivpu: Add firmware tracing support") Signed-off-by: Dawid Osuchowski Reviewed-by: Karol Wachowski Signed-off-by: Karol Wachowski Link: https://patch.msgid.link/20260901125749.404338-4-dawid.osuchowski@linux.intel.com Signed-off-by: Greg Kroah-Hartman Changed files: drivers/accel/ivpu/ivpu_fw_log.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=6dbba89df4e842d226f5cd3dbc5e94533cfceea2 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-97915 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97915 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:N/A:N The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:L The Best / paranoid CVSS score: 3.6 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: 2 Paranoid ActionableScore: 3 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).