CVE-2021-42090

CRITICAL 9.8CVE-2021-42090 · Published 07/10/2021 · updated 17/06/2026

In short

CVE-2021-42090 is a CRITICAL (CVSS 9.8) vulnerability affecting zammad (zammad).
Chance of exploitation in the next 30 days (EPSS): 2.3%, higher than 83.5% of all vulnerabilities.
Fix: update to 4.1.1 or later.

Package	Affected versions	Patched versions
zammad zammad	`< 4.1.1`	`4.1.1`

An issue was discovered in Zammad before 4.1.1. The Form functionality allows remote code execution because deserialization is mishandled.

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Package

Affected versions

Patched versions

< 4.1.1

4.1.1

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