Auth bypass in Zammad

CVE-2020-26030

An issue was discovered in Zammad before 3.4.1. There is an authentication bypass in the SSO endpoint via a crafted header, when SSO is not configured. An attacker can create a valid and authenticated session that can be used to perform any actions in the name of other users.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (70.4th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 70.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-26030: held from 0.013 to 0.013.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-26030?
CVE-2020-26030 is a critical-severity vulnerability in Zammad, classified under Improper Authentication. CVSS score: 9.8/10. Published 2020-12-28.
How severe is CVE-2020-26030?
Critical severity. CVSS v3 base score is 9.8 out of 10.