CVE-2026-6862
Efivar: efivar: denial of service due to stack overflow in device path node parsing
What happened?
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).
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| efivar-mainRed Hat | unaffected: 39-13.1.hum1 to < * | See vendor advisory |
| efivarRed Hat | Default status: unknown | See vendor advisory |
| efivarRed Hat | Default status: unknown | See vendor advisory |
| efivarRed Hat | Default status: unknown | See vendor advisory |
| efivarRed Hat | Default status: unknown | See vendor advisory |
| openshift/ose-rhel-coreos-8Red Hat | Default status: unknown | See vendor advisory |
| openshift/ose-rhel-coreos-9Red Hat | Default status: unknown | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.