From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-72143][LOW] platform/x86: ISST: Restore SST-PP control to all domains Date: Sun, 16 Aug 2026 06:56:57 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-72143 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: 0 X-AL-KERNEL-Commit: cea03d67db3a880893360bdbb1b0b8d9b33b1799 List-Id: CVE: CVE-2026-72143 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: platform/x86: ISST: Restore SST-PP control to all domains Commit: cea03d67db3a880893360bdbb1b0b8d9b33b1799 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=cea03d67db3a880893360bdbb1b0b8d9b33b1799 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72143 Analysis date: Sun, 16 Aug 2026 06:56:57 -0400 ActionableScore: 2 ActionableScore lower bound: 0 Actionable bucket: Ordinary Moderate / Low-like Manual review required: NO Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-72143 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72143 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-2026-72143 LOW CHECK WITH IMPACT FROM ORIG NN MODERATE 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:L/A:L';CWE-665;CWE-682;*CWE-664;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.4';DESCR 'Intel ISST TPMI resume handling can restore SST PP control to the wrong power domain because the saved control value is written using the base address for power domain 0 instead of the base address for the current domain. After suspend and resume, non zero power domains may keep stale or incorrect performance policy state, which can affect power or performance behavior on affected Intel systems. For the CVSS the PR:L is used in the paranoid case because some deployments may allow a local user or a power management service path to trigger suspend and resume, although direct ISST configuration is normally administrative. The issue is not network reachable and there is no evidence of memory corruption, UAF, OOB access, information disclosure, or privilege escalation. Impact is limited to availability or integrity of platform power policy state.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) YES SIMPLEFIX DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_GUESSCVSS_AND_CIANNH YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=2 ActionableScoreLower=0 1. ActionableScore * Conservative score: 0 * Paranoid score: 2 * Final recommended bucket: **Ordinary Moderate / Low-like**:: 2. Signal breakdown * Local unprivileged trigger: +1 in paranoid interpretation only. Some desktop or managed systems may allow a local user or power-management service path to trigger suspend/resume. * Integrity impact plausible: +1 in paranoid interpretation. Wrong SST-PP restore can leave non-zero power domains with incorrect performance policy state. * Availability impact realistic: +1 in paranoid interpretation. The likely impact is degraded or incorrect power/performance behavior after resume, not a kernel crash. * Requires admin/root/CAP_* in typical deployments: -2 in conservative interpretation. Direct ISST/platform power configuration is normally administrative. * Physical-only or rare hardware-only condition: -1 to -2. This requires affected Intel ISST TPMI hardware and suspend/resume behavior. No memory corruption, UAF, OOB access, refcount issue, arbitrary write primitive, sensitive data exposure, or privilege escalation path is supported by the patch. 3. Reachability analysis The bug is triggered through suspend/resume on affected Intel platforms with multiple power domains using ISST SST-PP control. In typical server deployments, controlling this platform state is administrative or service-managed, so conservative PR is high. In some desktop or managed environments, an unprivileged local user may indirectly trigger suspend/resume, so the paranoid interpretation allows local low-privilege reachability. Namespaces and containers do not materially lower reachability because this is platform firmware/device state, not a namespaced interface. The path is not network reachable. 4. Severity interpretation This behaves like a low-risk platform state restore bug, not an Important-class kernel vulnerability. The realistic impact is incorrect performance or power policy after resume. Theoretical impact is limited to platform policy integrity or availability degradation. There is no evidence of memory corruption or a practical privilege escalation primitive. 5. One-sentence report phrase Intel ISST TPMI resume handling may restore SST PP control using the power domain 0 base address for all domains, causing incorrect power or performance policy state after suspend and resume on affected systems. 6. Manual review recommendation NO MANUAL CHECK NEEDED. The issue is hardware-specific, not network reachable, and does not show memory corruption, sensitive-object access, privilege escalation, or a strong DoS primitive. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: platform/x86: ISST: Restore SST-PP control to all domains Commit: cea03d67db3a880893360bdbb1b0b8d9b33b1799 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=cea03d67db3a880893360bdbb1b0b8d9b33b1799 Commit description: The SST-PP control offset is only restored to power domain 0 after resume. During suspend, control values are read and stored for all power domains. Use pd_info->sst_base instead of power_domain_info->sst_base, which only points to power domain 0 base address. Fixes: dc7901b ("platform/x86: ISST: Store and restore all domains data") Reported-by: Yi Lai Signed-off-by: Srinivas Pandruvada Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260528204521.3531456-1-srinivas.pandruvada@linux.intel.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen Signed-off-by: Greg Kroah-Hartman Changed files: drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.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=cea03d67db3a880893360bdbb1b0b8d9b33b1799 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-72143 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72143 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:H/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:L/A:L The Best / paranoid CVSS score: 4.4 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: 0 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).