PT-2026-28805 · Pop Os · Cosmic-Greeter

Matthias Gerstner · Published 2026-03-30 · Updated 2026-04-19 · CVE-2026-25704

Positive Technologies (AI Summary)

CVSS v4.0

5.8

Medium

Base vector

AV:L/AC:H/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N

Name of the Vulnerable Software and Affected Versions cosmic-greeter versions prior to https://github.Com/pop-os/cosmic-greeter/pull/426

Description A Time-of-check Time-of-use (TOCTOU) race condition exists in cosmic-greeter. This condition can allow an attacker to regain privileges that should have been dropped and exploit vulnerabilities in the checking logic.

Recommendations Update cosmic-greeter to a version after https://github.Com/pop-os/cosmic-greeter/pull/426.

Fix

LPE

Time Of Check To Time Of Use

Weakness Enumeration

CWE-271

CWE-367

Related Identifiers

CVE-2026-25704

Affected Products

Cosmic-Greeter

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-25704 · Security Note
• http://openwall.com/lists/oss-security/2026/04/16/3 · Note
• https://bugzilla.suse.com/show_bug.cgi?id=CVE-2026-25704 · Note
• https://twitter.com/CVEnew/status/2038618089286160753 · Twitter Post
• https://twitter.com/oss_security/status/2045896408683720967 · Twitter Post