From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-97607][LOW] vdpa: ifcvf: Put device on unsupported feature error Date: Fri, 25 Sep 2026 16:36:47 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-97607 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: 2d7b5fbc7180dc9a0d105b97390422a11ccfe9cd List-Id: CVE: CVE-2026-97607 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: vdpa: ifcvf: Put device on unsupported feature error Commit: 2d7b5fbc7180dc9a0d105b97390422a11ccfe9cd Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2d7b5fbc7180dc9a0d105b97390422a11ccfe9cd Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97607 Analysis date: Fri, 25 Sep 2026 16:36:47 -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-2026-97607 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97607 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-2026-97607 LOW https://www.kernelcve.org/list/?q=CVE-2026-97607 CHECK WITH IMPACT FROM ORIG NN LOW 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-401;*CWE-772;**CWE-400;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.5';DESCR 'The ifcvf vDPA device creation path can return EINVAL for unsupported provisioned features after vdpa_alloc_device has already allocated the device. The direct return bypasses the common cleanup path and leaves the allocated vDPA device and adapter reference unreleased. Repeated failed creation requests may therefore accumulate leaked kernel resources and eventually cause availability degradation or resource exhaustion. For the CVSS the PR:L reflects that reliable triggering requires access to the local vDPA management interface, commonly through CAP_NET_ADMIN, which may be delegated to a container or restricted service account. The issue is not network reachable through ordinary packet traffic. The direct impact is a local resource leak with no supported UAF, OOB access, information disclosure, or write primitive. The base impact is A:L, while the paranoid A:H interpretation assumes sustained abuse can realistically exhaust host resources.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2) SKIP CVE-2026-97607 UNKNOWN SKIP The Fixes patch not applied yet, so unlikely that actual: 46fc0917bbab YES NO NO unknown MAYBE SIMPLEFIX ERRORPATH HARDWARE LINUS INCREASED_FROM_LOW_BASED_ON_HIGHCVSSSCORE DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=2 ActionableScoreLower=1 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES 1. ActionableScore * Raw conservative score: 1 * Conservative score: 1 * Raw paranoid score: 2 * Paranoid score: 2 * No floor or cap was applied. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown * +1 Concrete persistent kernel resource/reference leak. `vdpa_alloc_device()` succeeds, but the direct `-EINVAL` return bypasses the common error path that releases the device and adapter reference. * Paranoid +1 Resource exhaustion. Repeated invalid device-add requests can plausibly accumulate leaked allocations, although host-wide exhaustion is not directly demonstrated. * No UAF, repeated release, OOB access, arbitrary write, controlled reclaim, disclosure, or authorization bypass is established. * No crash point was awarded because the patch demonstrates a leak rather than an immediate kernel fault. * No remote-reachability point was awarded. This is a local vDPA management operation. * No C/I or exploitation-leverage points were awarded. * No privilege penalty was applied because the complete capability and host-administration boundary is not established by the supplied context. 3. Reachability analysis Triggering requires a local request to create an ifcvf vDPA device with unsupported provisioned feature bits. The management interface is capability-gated, but the supplied evidence does not prove whether the complete operation requires host-admin-equivalent control or can be performed through delegated or namespace-scoped `CAP_NET_ADMIN`. The underlying ifcvf management device is normally associated with provisioned device state, so prior device availability is required. No direct packet-triggered or remote path exists. No race or special timing is involved, and repeated requests appear possible once management access is available. 4. Primitive and severity interpretation The exact primitive is a persistent allocation/reference leak caused by bypassing the common cleanup path after `vdpa_alloc_device()`. There is no stale post-lifetime use, double release, active-object corruption, or second refcount mutation. Therefore `RealUAF=NO` and the issue is `CLASS_C`, reflecting resource-exhaustion-oriented behavior without an independently useful corruption primitive. The demonstrated consequence is leaked kernel resources. Sustained exhaustion is a defensible paranoid consequence, but immediate host-wide DoS is not established. There is no evidence of confidentiality, integrity, privilege-escalation, or security-boundary impact. `ImportantCandidate=NO` and `AutoDowngradeAllowed=YES` because no unresolved corruption or authorization primitive remains. 5. One-sentence report phrase An unsupported feature request can bypass ifcvf vDPA device cleanup after allocation, leaking the device and adapter reference and potentially causing resource exhaustion after repeated local management requests. 6. Manual review recommendation NO MANUAL CHECK NEEDED The patch establishes a conventional local resource leak without UAF, memory corruption, authorization bypass, or Important-grade exploitation leverage. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: vdpa: ifcvf: Put device on unsupported feature error Commit: 2d7b5fbc7180dc9a0d105b97390422a11ccfe9cd Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2d7b5fbc7180dc9a0d105b97390422a11ccfe9cd Commit description: Route unsupported provisioned features through the common error path after vdpa_alloc_device() so the allocated device and adapter pointer are released consistently. Fixes: 46fc091 ("vDPA/ifcvf: implement features provisioning") Cc: stable@vger.kernel.org # v6.3+ Signed-off-by: Xiong Weimin Signed-off-by: Michael S. Tsirkin Message-ID: <178589471294.1556376.4816776800128323034@kylinos.cn> Signed-off-by: Greg Kroah-Hartman Changed files: drivers/vdpa/ifcvf/ifcvf_main.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=2d7b5fbc7180dc9a0d105b97390422a11ccfe9cd ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-97607 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97607 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:L/UI:N/S:U/C:N/I:N/A:L 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: 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).