It seems there was some kind of confusion during the disclosure process, because the vendors aren't treating this vulnerability as serious and it remains unpatched in many distros.
https://access.redhat.com/security/cve/cve-2026-31431 "Moderate severity", "Fix deferred"
https://security-tracker.debian.org/tracker/CVE-2026-31431
RedHat has also changed it to "Important severity" and "Affected" now.
Yeah, by ubuntu's own guidelines linked on that page, this should be priority: high, but instead it's marked as medium.
Seems like distros consider it a medium risk because it doesn't involve remote code execution and requires local access. Though it allows local root privilege escalation which is considered high priority.
https://ubuntu.com/security/cves/about#priority
> Medium: A significant problem, typically exploitable for many users. Includes network daemon denial of service, cross-site scripting, and gaining user privileges.