CVE-2026-43344: Linux kernel · perf/x86/intel/uncore: Fix die ID init and look up bugs
Source GCVE Database
Not known to be exploited · CVSS 5.5 Low · fixed in c79ef3342632e71ac8612a2a1cc17ac84dd258b4 : update Linux kernel when convenient.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none- Patch
- Available – fixed in c79ef3342632e71ac8612a2a1cc17ac84dd258b4, bdb35811ff41a1678620a407056b6372f350028a, a16d1ec4dd0cdcf689f324adde6067083bce9099 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: perf/x86/intel/uncore: Fix die ID init and look up bugs In snbep_pci2phy_map_init(), in the nr_node_ids > 8 path, uncore_device_to_die() may return -1 when all CPUs associated with the UBOX device are offline. Remove the WARN_ON_ONCE(die_id == -1) check for two reasons: - The current code breaks out of the loop. This is incorrect because pci_get_device() does not guarantee iteration in domain or bus order, so additional UBOX devices may be skipped during the scan. - Returning -EINVAL is incorrect, since marking offline buses with die_id == -1 is expected and should not be treated as an error. Separately, when NUMA is disabled on a NUMA-capable platform, pcibus_to_node() returns NUMA_NO_NODE, causing uncore_device_to_die() to return -1 for all PCI devices. As a result, spr_update_device_location(), used on Intel SPR and EMR, ignores the corresponding PMON units and does not add them to the RB tree. Fix this by using uncore_pcibus_to_dieid(), which retrieves topology from the UBOX GIDNIDMAP register and works regardless of whether NUMA is enabled in Linux. This requires snbep_pci2phy_map_init() to be added in spr_uncore_pci_init(). Keep uncore_device_to_die() only for the nr_node_ids > 8 case, where NUMA is expected to be enabled.
References
- nvd.nist.gov/vuln/detail/CVE-2026-43344 (opens in a new tab)
- git.kernel.org/stable/c/184870af0e73f8ea2577c751fa098681465249f2 (opens in a new tab)
- git.kernel.org/stable/c/4eb511275e37c580156e787baab5232aeb0bfea0 (opens in a new tab)
- git.kernel.org/stable/c/6a5dc3ee97581da2907fc7acd62853f07184de67 (opens in a new tab)
- git.kernel.org/stable/c/a16d1ec4dd0cdcf689f324adde6067083bce9099 (opens in a new tab)
- git.kernel.org/stable/c/bdb35811ff41a1678620a407056b6372f350028a (opens in a new tab)
- git.kernel.org/stable/c/c79ef3342632e71ac8612a2a1cc17ac84dd258b4 (opens in a new tab)