CVE-2026-21891 is a critical authentication bypass vulnerability affecting ZimaOS versions up to and including 1.5.0. This flaw allows unauthenticated attackers to gain full access to affected systems by providing any password when logging in with known system service account usernames. With a CVSS score of 9.8, this vulnerability presents a high risk due to its network-based attack vector, low complexity, and complete compromise of confidentiality, integrity, and availability. While not yet in CISA's KEV catalog, public Nuclei templates exist for exploitation, and it has garnered some community discussion, indicating potential for future active exploitation.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
<= 1.5.0CPE matchmatch criteria | cpe:2.3:o:zimaspace:zimaos:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.