From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-53203][IMPORTANT] accel/ivpu: Add buffer overflow check in MS get_info_ioctl Date: Thu, 25 Jun 2026 20:38:46 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-53203 X-AL-KERNEL-Priority: IMPORTANT X-AL-KERNEL-Severity: IMPORTANT X-AL-KERNEL-Base-Severity: IMPORTANT X-AL-KERNEL-KPANIC: YES X-AL-KERNEL-ActionableScore: 7 X-AL-KERNEL-ActionableScore-Lower: 6 X-AL-KERNEL-Commit: d3c12ed33e8923f3090909a1738f3e59292996a6 List-Id: CVE: CVE-2026-53203 Priority: IMPORTANT AL-KERNEL base severity: IMPORTANT KPANIC flag: YES Patch: accel/ivpu: Add buffer overflow check in MS get_info_ioctl Commit: d3c12ed33e8923f3090909a1738f3e59292996a6 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d3c12ed33e8923f3090909a1738f3e59292996a6 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53203 Analysis date: Thu, 25 Jun 2026 20:38:46 -0400 ActionableScore: 7 ActionableScore lower bound: 6 Actionable bucket: Strong Important candidate / Actionable Moderate at minimum Manual review required: YES Summary: A local ivpu device user can trigger a firmware-size driven buffer overflow in the metric stream get_info ioctl when info_size exceeds the actual BO allocation, causing at least kernel memory corruption or DoS and requiring manual review for possible LPE. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-53203 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53203 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: IMPORTANT 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-2026-53203 IMPORTANT CHECK Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H';*CWE-787;CWE-120;*CWE-20;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H';BEST CVSS score: '7.8';DESCR 'A buffer overflow risk exists in the ivpu metric stream get_info ioctl because the firmware reported info_size was compared with the user supplied buffer_size but was not checked against the actual allocated buffer object size. A local process with access to the ivpu accel device can provide a buffer object that is smaller than the returned metric stream info while still passing a larger buffer_size, which may let the driver proceed with an incorrect copy beyond the allocated buffer. For the CVSS the PR:L is used because triggering requires local access to the ivpu ioctl path through a process that can open the accelerator device, but it does not normally require full administrator privileges. The issue is not network reachable. Impact is at least denial of service via memory corruption or kernel crash, and a higher integrity or confidentiality impact is plausible enough for manual review because the patch context explicitly addresses a buffer overflow condition.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 7) SKIP CVE-2026-53203 SKIP The Fixes patch not applied yet, so unlikely that actual: cdfad4db7756563db7d458216d9e3c2651dddc7d YES NO NO unknown MAYBE OOB SIMPLEFIX KPANIC KPANIC INCREASED_TO_HIGH_BASED_ON_GUESSCVSS - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=7 ActionableScoreLower=6 ## 1. ActionableScore * Conservative score: 6 * Paranoid score: 7 * Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**:: ## 2. Signal breakdown * Local unprivileged trigger: +1 The bug is reachable through the ivpu metric stream get_info ioctl by a local process with access to the accel or DRM device node. * Firmware-mediated external influence: +1 The dangerous size value is returned from firmware. This is not network reachable, but the kernel trusts firmware-provided metadata in a device-management path. * Constrained kernel buffer overwrite: +1 conservative The patch explicitly prevents proceeding when firmware returned info_size exceeds the allocated BO size. The overflow target appears to be a driver buffer object, but target and payload control are not clearly arbitrary. * Generic memory corruption: +2 paranoid The commit describes a buffer overflow check, and the missing bound is against the actual allocation size. For paranoid triage this is defensibly treated as kernel memory corruption. * Weak LPE concern: +1 conservative A local ioctl-accessible buffer overflow in a kernel accelerator driver can plausibly become more than a crash, but the patch does not show a demonstrated reclaim, arbitrary write, or controlled target primitive. * Privilege escalation plausible: +2 paranoid For the paranoid score, a kernel buffer overflow reachable by a local device-node user is enough to avoid auto-closing without manual review. * Privileged kernel/device-management memory corruption path: +1 The corruption occurs in a trusted accelerator driver path involving firmware-fed metadata and kernel-managed BO allocation state. * Reliable kernel crash / strong DoS: +1 Proceeding with a copy larger than the allocated BO can realistically crash or corrupt kernel/device memory. * Integrity impact plausible: +1 conservative Out-of-bounds writes can corrupt adjacent state, although the exact target is not demonstrated. * Rare AND difficult-to-reach subsystem/configuration: -1 Exposure depends on Intel ivpu hardware, NPU profiling support, and access to the relevant device node. ## 3. Reachability analysis The likely attacker is a local user or local process that can open the ivpu accel or DRM device and invoke the metric stream get_info ioctl. This should not be scored as PR:H by default, because accelerator or render-style device nodes are often exposed to non-root local users through device ACLs or groups. It is not remotely network reachable. Namespaces and containers may matter if the device node is passed into a container. A container user with access to the ivpu device could potentially reach the same ioctl path without full host-root privileges. The path is not universally default-exposed because it requires affected hardware, the ivpu driver, and NPU profiling support introduced by the referenced commit. ## 4. Severity interpretation This is stronger than an ordinary Moderate because the patch fixes an allocation-size check missing before a buffer copy in a kernel driver ioctl path. The realistic evidence supports local DoS and constrained memory corruption. The paranoid interpretation treats it as an Important candidate because local kernel buffer overflows in device drivers can sometimes be turned into privilege escalation, even when the immediate patch does not demonstrate arbitrary write or object-reclaim control. Overall, this should not be auto-closed as a low-risk crash-only issue. ## 5. One-sentence report phrase A local ivpu device user can trigger a firmware-size driven buffer overflow in the metric stream get_info ioctl when info_size exceeds the actual BO allocation, causing at least kernel memory corruption or DoS and requiring manual review for possible LPE. ## 6. Manual review recommendation MANUAL CHECK REQUIRED Reason: the patch explicitly fixes a buffer overflow boundary check in a local ioctl-accessible kernel accelerator driver path, with firmware-fed size metadata and plausible local privilege escalation concern despite limited evidence of a strong controlled-write primitive. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: accel/ivpu: Add buffer overflow check in MS get_info_ioctl Commit: d3c12ed33e8923f3090909a1738f3e59292996a6 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d3c12ed33e8923f3090909a1738f3e59292996a6 Commit description: Add validation that the info size returned from the metric stream info query is not exceeded when checked against the allocated buffer size. If the firmware returns a size larger than the buffer, reject the operation with -EOVERFLOW instead of proceeding with an incorrect buffer copy. Fixes: cdfad4d ("accel/ivpu: Add NPU profiling support") Cc: stable@vger.kernel.org # v6.18+ Signed-off-by: Andrzej Kacprowski Reviewed-by: Karol Wachowski Signed-off-by: Karol Wachowski Link: https://patch.msgid.link/20260529120841.135852-1-andrzej.kacprowski@linux.intel.com Signed-off-by: Greg Kroah-Hartman Changed files: drivers/accel/ivpu/ivpu_ms.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=d3c12ed33e8923f3090909a1738f3e59292996a6 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-53203 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53203 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:L/I:L/A:H The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H The Best / paranoid CVSS score: 7.8 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: 6 Paranoid ActionableScore: 7 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: IMPORTANT KPANIC detected for this report: YES Published priority for this report (same as in Subject): IMPORTANT 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).