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).

A stack overflow vulnerability was found in libefiboot (part of efivar). The device path node parser does not validate that each node Length field is >= 4 bytes (minimum EFI device path node header size) before recursing. A crafted node with Length < 4 causes infinite recursion in efiloadoptisvalid() -> efiloadoptoptionaldatasize(), leading to stack exhaustion and process crash.

Upstream: github.com/rhboot/efivar - no Issues tab or SECURITY.md available. This report serves as initial upstream notification. Suggested fix: Add minimum length guard: if (dp->length < 4) return -1;