CVE-2026-90379: Linux kernel · wifi: mt76: mt7921: Add PCIe AER handler support to prevent system crash
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available that validates DMA indices and handles bus hang conditions more robustly to prevent invalid memory accesses and system crashes. Users should apply the updated Linux kernel versions containing this patch. No additional mitigation is indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's mt76 Wi-Fi driver for the mt7921 device has been resolved. The issue occurs when a PCIe Advanced Error Reporting (AER) error causes the bus to hang, leading to register reads returning 0xFFFFFFFF. This corrupts the DMA queue state and results in invalid memory access, potentially causing system crashes. The fix involves validating DMA indices before use, clamping out-of-range values, checking the bus_hung flag before reset sequences, rejecting MCU messages during bus hang, and installing no-op bus operations after unrecoverable AER errors. Due to hardware limitations, some affected Wi-Fi devices may not fully recover after certain errors even with AER enabled.
References
- nvd.nist.gov/vuln/detail/CVE-2026-90379 (opens in a new tab)
- git.kernel.org/stable/c/670b3dc4e3713542a9f002d38fb9d1740b9e342b (opens in a new tab)
- git.kernel.org/stable/c/915672c5ae32deeb72f4572856d123f314791136 (opens in a new tab)
- git.kernel.org/stable/c/f544bcba4721e1074e9bc6666f0ef4f8b96ddba8 (opens in a new tab)
- ubuntu.com/security/CVE-2026-90379 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-90379 (opens in a new tab)
- git.kernel.org/linus/915672c5ae32deeb72f4572856d123f314791136 (opens in a new tab)