CVE-2026-6862

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).

Moderate impact. A stack overflow vulnerability in libefiboot (part of efivar) can lead to a process crash due to unbounded recursion when parsing a specially crafted device path node. This flaw affects Red Hat Enterprise Linux 8, 9, and 10, as well as Fedora and OpenShift Container Platform.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Applications using efi_loadopt_is_valid() should validate the size of the input buffer before passing it to libefiboot. As a library-level fix, the device path iterator should enforce a minimum node Length of 4 before recursing:

if (dp->length < 4) return -1;