CVE-2026-43344
Linux Kernel perf/x86/intel/uncore Die ID Initialization Bug
Publication date: 2026-05-08
Last updated on: 2026-05-18
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | From 5.12 (inc) to 6.19.14 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-617 | The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability involves the Linux kernel's handling of Intel uncore devices in the perf/x86/intel/uncore subsystem. Specifically, in the function snbep_pci2phy_map_init(), when the number of node IDs is greater than 8, the function uncore_device_to_die() may return -1 if all CPUs associated with a UBOX device are offline. This causes incorrect behavior because the code treats this as an error and breaks out of a loop, potentially skipping additional UBOX devices during scanning.
Additionally, when NUMA (Non-Uniform Memory Access) is disabled on a NUMA-capable platform, uncore_device_to_die() returns -1 for all PCI devices, causing certain PMON units to be ignored and not added to the RB tree, which affects device location updates.
The fix involves removing the erroneous error check for die_id == -1, and using a different method, uncore_pcibus_to_dieid(), to retrieve topology information regardless of NUMA being enabled or disabled. This ensures proper scanning and handling of UBOX devices and PMON units.
How can this vulnerability impact me? :
This vulnerability can lead to incomplete or incorrect detection and handling of Intel uncore devices in the Linux kernel, particularly UBOX devices and PMON units. As a result, performance monitoring and device topology information may be inaccurate or incomplete.
Such inaccuracies could affect system monitoring, performance analysis, and potentially the stability or efficiency of systems relying on accurate hardware topology and performance data, especially on NUMA-capable platforms or when NUMA is disabled.
What immediate steps should I take to mitigate this vulnerability?
The vulnerability is fixed by updating the Linux kernel to a version that includes the patch resolving the issue in perf/x86/intel/uncore, specifically addressing the handling of die ID initialization and lookup bugs.
Immediate mitigation involves applying the updated kernel where snbep_pci2phy_map_init() uses uncore_pcibus_to_dieid() to correctly retrieve topology regardless of NUMA settings, and removing the incorrect WARN_ON_ONCE(die_id == -1) check.