From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98560][LOW] net/rds: size a connection's path set by the transport it ends up with [ Upstream Date: Sat, 24 Oct 2026 07:34:15 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98560 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: 670f303169d2d36f315c40f6d3d18b5ee8498fea List-Id: CVE: CVE-2026-98560 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: net/rds: size a connection's path set by the transport it ends up with [ Upstream Commit: 670f303169d2d36f315c40f6d3d18b5ee8498fea Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=670f303169d2d36f315c40f6d3d18b5ee8498fea Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98560 Analysis date: Sat, 24 Oct 2026 07:34:15 -0400 ActionableScore: 1 ActionableScore lower bound: unknown Actionable bucket: Ordinary Moderate Manual review required: NO Summary: RDS transport substitution can permanently leak seven ordered workqueues per local loopback-selected connection, enabling possible cumulative resource pressure without demonstrated memory corruption or host-wide failure. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98560 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98560 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-2026-98560 LOW https://www.kernelcve.org/list/?q=CVE-2026-98560 CHECK WITH IMPACT FROM ORIG NN IMPORTANT | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=1 LEGACY=LOW RESULT=DIFF TEMP_DISTANCE_MERGE_SKIP=AEGIS_NO_POSITIVE_SEVERITY_EVIDENCE (final Legacy and Aegis differ; FINAL: LOW, Aegis: MODERATE_KPANIC) Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';*CWE-401;*CWE-772;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'An RDS TCP connection to a local address can be switched to the loopback transport after its path count was calculated. Creation then allocates ordered workqueues for all TCP multipath entries, while teardown follows the final loopback transport and releases only path 0, leaving seven workqueues permanently unreachable for each affected connection. The demonstrated primitive is persistent kernel resource retention rather than UAF, OOB access, or other memory corruption. For the CVSS the PR:L value assumes a local user can access RDS and can use delegated or unprivileged user and network namespaces to reach the required teardown cycle. Attack complexity is high because exploitation depends on RDS TCP configuration, suitable local destination addresses, connection creation, and repeatable namespace teardown or module lifecycle operations. Host wide exhaustion is possible only under sustained and repeatable accumulation and is not established by the patch evidence. Automated impact decision path. The original SimpleNet classifier selected IMPORTANT. The primary LLM estimated paranoid CVSS 4.7 and the production ActionableScore returned 1 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were CVSS and initial triage stage IMPORTANT to MODERATE_KPANIC because the CVSS score, vector or bug class threshold rule was applied. ActionableScore thresholds stage MODERATE_KPANIC to LOW because the ActionableScore threshold rule was applied. final reconciliation stage LOW to LOW because KP specialist did not establish a qualifying panic and the cross model evidence reconciliation rule was applied. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. Exact triggered rule markers were LOWERED_FROM_HIGH_BASED_ON_GUESSCVSS and DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 and DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 and KPANIC_UNSUPPORTED_REMOVED and V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED. The independent weaker Aegis shadow evaluated CVSS 3.3 and ActionableScore 1 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE_KPANIC. The models disagreed but the aggregation rules retained the production result. The final reported impact is LOW.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1) MAYBE OOB UAF LINUS LOWERED_FROM_HIGH_BASED_ON_GUESSCVSS DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 KPANIC_UNSUPPORTED_REMOVED V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=1 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw base score: 1 * Conservative score: 1; no floor or cap applied. * Raw paranoid score: 1 * Paranoid score: 1; host-wide exhaustion is not sufficiently established for an additional DoS point. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown * **+1 Concrete persistent kernel resource/ref leak:** transport substitution leaves seven allocated ordered workqueues unreachable per affected connection. Destruction follows the final loopback transport and does not destroy those extra workqueues. * **+0 Reliable kernel crash/strong DoS:** sustained accumulation could pressure kernel resources, but neither a crash nor host-wide exhaustion is demonstrated. * **+0 Local unprivileged trigger:** the patch does not establish that an ordinary user can complete RDS setup, local connection creation, and repeatable teardown. * No OOB read/write, UAF, double release, attacker-controlled corruption, authorization bypass, confidentiality impact, or integrity impact is shown. * NEW52/B5-R does not apply: there is no retry-accumulated heap OOB write or later consumption of corrupted structured state. * No privilege, race, rarity, or hardware penalty is applied because the necessary restrictions are not positively proved. 3. Reachability analysis An RDS/TCP connection to a local address triggers the allocation mismatch. Repetition can occur across distinct local destinations and connection lifecycles. Module unload is host-administrative, while netns teardown may offer another route, but the evidence does not establish that the complete RDS configuration, connection, and teardown sequence is available through attacker-created namespaces. Therefore both effective host-admin requirement and namespace-scoped privilege remain unknown. No special hardware or timing race is required. 4. Primitive and severity reading The exact primitive is persistent leakage of seven kernel workqueues per affected connection due to inconsistent creation and destruction path counts. It is resource-retention/DoS behavior, not memory corruption or a stale-object use, so it is CLASS_C. Potential cumulative exhaustion is plausible but unproven. There is no useful non-crash corruption primitive or unknown trust-boundary chain requiring Important preservation. Consequently ImportantCandidate is NO and automatic Moderate downgrade is allowed. 5. One-sentence report phrase RDS transport substitution can permanently leak seven ordered workqueues per local loopback-selected connection, enabling possible cumulative resource pressure without demonstrated memory corruption or host-wide failure. 6. Manual review advice NO MANUAL CHECK NEEDED The patch establishes a bounded-per-connection resource leak but no Important-preserving primitive or confirmed strong DoS. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: net/rds: size a connection's path set by the transport it ends up with [ Upstream Commit: 670f303169d2d36f315c40f6d3d18b5ee8498fea Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=670f303169d2d36f315c40f6d3d18b5ee8498fea Changed files: net/rds/connection.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=670f303169d2d36f315c40f6d3d18b5ee8498fea ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98560 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98560 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:L/UI:N/S:U/C:N/I:N/A:L The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 4.7 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).