What is CVE-2021-42087?

CVE-2021-42087 is a medium-severity vulnerability in Zammad. CVSS score: 4.9/10. Published 2021-10-07.

How severe is CVE-2021-42087?

Medium severity. CVSS v3 base score is 4.9 out of 10.

Vulnerability in Zammad

CVE-2021-42087

An issue was discovered in Zammad before 4.1.1. An admin can discover the application secret via the API.

Published 2021-10-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.009 (57.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Zammad

References

zammad.com/en/advisories/zaa-2021-15 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-42087?: CVE-2021-42087 is a medium-severity vulnerability in Zammad. CVSS score: 4.9/10. Published 2021-10-07.
How severe is CVE-2021-42087?: Medium severity. CVSS v3 base score is 4.9 out of 10.