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CVE-2026-6862 (GCVE-0-2026-6862)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:45 – Updated: 2026-09-01 08:38
VLAI
Title
Efivar: efivar: denial of service due to stack overflow in device path node parsing
Summary
A flaw was found in libefiboot, a component of efivar. The device path node parser in libefiboot fails to validate that each node's Length field is at least 4 bytes, which is the minimum size for an EFI (Extensible Firmware Interface) device path node header. A local user could exploit this vulnerability by providing a specially crafted device path node. This can lead to infinite recursion, causing stack exhaustion and a process crash, resulting in a denial of service (DoS).
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-22 14:28 UTC
CWE
Assigner
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-6862 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2459982 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-04-09 00:00
Credits
Red Hat would like to thank Mathis Huron (Oteria Cyber School, FuzzingLabs) for reporting this issue.
Show details on NVD website
To clipboard 

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