From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-92525][MODERATE REGULAR] RDMA/rxe: Validate num_sge/cur_sge before indexing wqe->dma.sge[] [ Upstream Date: Fri, 18 Sep 2026 09:04:23 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-92525 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: 4 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: 69d3ccf6543f24c452a020c8028ca6f46cb1e8db List-Id: CVE: CVE-2026-92525 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: RDMA/rxe: Validate num_sge/cur_sge before indexing wqe->dma.sge[] [ Upstream Commit: 69d3ccf6543f24c452a020c8028ca6f46cb1e8db Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=69d3ccf6543f24c452a020c8028ca6f46cb1e8db Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-92525 Analysis date: Fri, 18 Sep 2026 09:04:23 -0400 ActionableScore: 4 ActionableScore lower bound: unknown 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-2026-92525 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-92525 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-2026-92525 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-92525 CHECK WITH IMPACT FROM ORIG NN IMPORTANT Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H';CWE-125;CWE-129;*CWE-20;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '6.1';DESCR 'A vmalloc out-of-bounds read in the RDMA rxe requester path can occur because a user QP WQE is read from an mmap ring controlled by userspace and num_sge or cur_sge were not validated before indexing wqe dma sge in copy_data(). A local user with access to the rxe RDMA device can post a malformed WQE with an out-of-range cur_sge or oversized num_sge and trigger an invalid kernel read. For the CVSS the PR:L is used because triggering requires a local user or process with access to the RDMA userspace interface, but not full administrative privileges. The issue is not directly network reachable because the malformed state is supplied through the local user QP ring rather than by remote packets. Impact is at least local denial of service via kernel crash or KASAN-detected fault, with limited confidentiality impact considered in the paranoid score due to the concrete invalid read primitive.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 4) YES WRITE KASAN OOB SIMPLEFIX NETWORK LINUS MEMORY LOWERED_FROM_HIGH_BASED_ON_GUESSCVSS DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP NO NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=4 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=NO NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES 1. ActionableScore * Raw conservative score: 4 * Conservative score: 4 * Raw paranoid score: 4 * Paranoid score: 4 * Final recommended bucket: **Borderline / manual review recommended**:: No floor or cap changed the score. 2. Signal breakdown Positive signals: * +1 Local unprivileged trigger: the supplied context explicitly says a local unprivileged user can post a malformed user QP WQE through the mmaped SQ ring. * +1 Local unprivileged high-control kernel data-plane API: userspace directly controls num_sge and cur_sge in the WQE, which are exploitation-relevant indices consumed by rxe_requester() and copy_data(). * +1 Weak / indirect corruption candidate: the primitive is an attacker-controlled unchecked index into wqe->dma.sge[], producing a vmalloc out-of-bounds read. * +1 Reliable kernel crash / strong DoS: the issue was reproduced under KASAN as a vmalloc-out-of-bounds read, and the described practical consequence is local DoS. Negative signals: * 0 No host-admin penalty: the supplied evidence positively states local unprivileged reachability. * 0 No race penalty: this is not a timing race. * 0 No niche-subsystem penalty: RDMA/rxe is optional, but no concrete evidence shows a rare or physical-only prerequisite that should reduce the score. Important non-awarded signals: * Controlled reclaim not demonstrated. * Arbitrary write not demonstrated. * Real UAF not demonstrated. * Concrete repeated release/refcount mutation not present. * Confidentiality not awarded because no read-back or disclosure path is established. * Integrity not awarded because no unauthorized modification primitive is established. * Strong LPE / strong exploitation leverage not awarded because the patch supports an invalid read and DoS, not controlled corruption. * Extra Availability not awarded because the same crash/KASAN fault is already counted once. * Remote reachability not awarded because the malformed state is supplied through the local userspace QP ring, not by remote packets. 3. Reachability analysis The evaluated attacker is a local user with access to the rxe RDMA userspace interface. The supplied text states that a user QP uses qp->sq.queue as a ring directly written by the application, and that rxe_post_send() does not validate the user WQE before scheduling send_task. Host administrator privilege is not required according to the supplied evidence, so HostAdminRequired=NO. Namespace-scoped privilege is not the relevant boundary here, and no complete namespace-based trigger chain is needed or established, so NamespaceScopedPrivilege=NO. No prior privileged setup is scored as a reducing condition beyond the existence of the rxe device/interface, because the input already establishes local unprivileged triggering. No special physical hardware-only requirement is established. This is not a race, and the trigger appears sequence-based and repeatable by posting malformed WQEs. 4. Primitive and severity interpretation The exact primitive is a vmalloc out-of-bounds read caused by using attacker-controlled num_sge or cur_sge before validating them against qp->sq.max_sge. The stale/lifetime categories do not apply because no UAF, RCU lifetime violation, double release, or refcount misuse is shown. This is an active kernel data-path bug in the RDMA rxe requester, but the established primitive is read-only OOB access with demonstrated crash behavior. It is not a fixed stale-storage UAF and not a cleanup/destructor lifetime bug. PrimitiveClass=CLASS_C because the demonstrated behavior is primarily invalid read / crash / DoS without an independently useful corruption, disclosure, write, ownership, or boundary-bypass primitive. The demonstrated consequence is local denial of service. The speculative consequence would be stronger exploitation if the OOB read could be connected to controlled structured reinterpretation, disclosure, or subsequent memory corruption, but that is not established by the supplied patch/context. ImportantCandidate=NO because this is not Class A and does not establish a strong unresolved Class B lifetime/corruption primitive. AutoDowngradeAllowed=YES because the established issue is a constrained local OOB read / DoS with no UAF, no repeated lifetime mutation, no controlled write, no disclosure path, and no security-boundary bypass. Likely operational severity is borderline Moderate: it should be reviewed because it is local unprivileged kernel OOB access, but the available evidence does not support Important-class scoring. 5. One-sentence report phrase A local unprivileged user with access to the RDMA rxe userspace interface can place malformed num_sge or cur_sge values in a user QP WQE, causing copy_data() to perform a vmalloc out-of-bounds read and potentially crash the kernel. 6. Manual review recommendation MANUAL CHECK RECOMMENDED Reason: this is a concrete local unprivileged kernel OOB read in a userspace-controlled data path, but current evidence supports DoS only and does not establish disclosure, write corruption, UAF, or privilege escalation. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: RDMA/rxe: Validate num_sge/cur_sge before indexing wqe->dma.sge[] [ Upstream Commit: 69d3ccf6543f24c452a020c8028ca6f46cb1e8db Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=69d3ccf6543f24c452a020c8028ca6f46cb1e8db Changed files: drivers/infiniband/sw/rxe/rxe_req.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=69d3ccf6543f24c452a020c8028ca6f46cb1e8db ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-92525 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-92525 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:H The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H The Best / paranoid CVSS score: 6.1 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: 4 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).