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VulnerabilityPublished Updated

CVE-2026-23467: Linux kernel · drm/i915/dmc: Fix an unlikely NULL pointer deference at probe

Affects Linux kernelSource CVE Database V5

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Not known to be exploited · fixed in ac57eb3b7d2ad649025b5a0fa207315f755ac4f6 : update Linux kernel when convenient.

Data as of 5 Nov 2026, 23:24 UTC

Severity
Unrated

Rated by Threat Radar · No CVSS score from NVD or the CNA

Thin evidence

One scorer or none
EPSS
0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CISA SSVC
Exploitation
No evidence of active exploitation and no public proof of concept
Automatable
Attackers cannot reliably automate steps 1–4 of the kill chain
Technical impact
Limited control over the software or limited information exposure

CISA SSVC assessment, 2026-11-05.

Patch
Available – fixed in ac57eb3b7d2ad649025b5a0fa207315f755ac4f6, 631317825d44283abfe7a8374f13a76ce2032bb8, 0b35d11fbbcfd1079c8489282a341944228835e3

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 3 Apr 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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 5 Nov 2026.

What to do

Upgrade Linux kernel to ac57eb3b7d2ad649025b5a0fa207315f755ac4f6, 631317825d44283abfe7a8374f13a76ce2032bb8 or 0b35d11fbbcfd1079c8489282a341944228835e3.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 88c1f9a4d36de61f87cc52aac670020b13d1ccaa, < ac57eb3b7d2ad649025b5a0fa207315f755ac4f6
Fixed in
  • ac57eb3b7d2ad649025b5a0fa207315f755ac4f6
LinuxLinuxAffected
  • ≥ 88c1f9a4d36de61f87cc52aac670020b13d1ccaa, < 631317825d44283abfe7a8374f13a76ce2032bb8
Fixed in
  • 631317825d44283abfe7a8374f13a76ce2032bb8
LinuxLinuxAffected
  • ≥ 88c1f9a4d36de61f87cc52aac670020b13d1ccaa, < 0b35d11fbbcfd1079c8489282a341944228835e3
Fixed in
  • 0b35d11fbbcfd1079c8489282a341944228835e3
LinuxLinuxAffected
  • =6.16
Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: drm/i915/dmc: Fix an unlikely NULL pointer deference at probe intel_dmc_update_dc6_allowed_count() oopses when DMC hasn't been initialized, and dmc is thus NULL. That would be the case when the call path is intel_power_domains_init_hw() -> {skl,bxt,icl}_display_core_init() -> gen9_set_dc_state() -> intel_dmc_update_dc6_allowed_count(), as intel_power_domains_init_hw() is called *before* intel_dmc_init(). However, gen9_set_dc_state() calls intel_dmc_update_dc6_allowed_count() conditionally, depending on the current and target DC states. At probe, the target is disabled, but if DC6 is enabled, the function is called, and an oops follows. Apparently it's quite unlikely that DC6 is enabled at probe, as we haven't seen this failure mode before. It is also strange to have DC6 enabled at boot, since that would require the DMC firmware (loaded by BIOS); the BIOS loading the DMC firmware and the driver stopping / reprogramming the firmware is a poorly specified sequence and as such unlikely an intentional BIOS behaviour. It's more likely that BIOS is leaving an unintentionally enabled DC6 HW state behind (without actually loading the required DMC firmware for this). The tracking of the DC6 allowed counter only works if starting / stopping the counter depends on the _SW_ DC6 state vs. the current _HW_ DC6 state (since stopping the counter requires the DC5 counter captured when the counter was started). Thus, using the HW DC6 state is incorrect and it also leads to the above oops. Fix both issues by using the SW DC6 state for the tracking. This is v2 of the fix originally sent by Jani, updated based on the first Link: discussion below. (cherry picked from commit 2344b93af8eb5da5d496b4e0529d35f0f559eaf0)

References

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