OESA-2026-4838: efivar security update
Some command line interface of the UEFI variables tools are offered by . Security Fix(es):
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).(CVE-2026-6862)
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
openeuler/efivarto a version that resolves this vulnerability.Fixed in 38-9.oe2203sp4
Event History
Frequently Asked Questions
Who is realistically exposed to this issue?
Systems with the affected efivar/libefiboot UEFI variable tools available to local users are exposed. Exploitation requires local access; the provided severity vector does not indicate network-based exploitation.
What does an attacker need to exploit it?
An attacker needs to provide a specially crafted EFI device path node to the vulnerable parser. No privileges are indicated as required, but user interaction is required according to the supplied severity vector.
What is the impact of successful exploitation?
A malformed device path node with a Length field smaller than 4 bytes can trigger infinite recursion. This exhausts the process stack and crashes the process, causing a denial of service.