How severe is CVE-2021-42086?

CVE-2021-42086 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-42086 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42086?

CVE-2021-42086 affects Zammad. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42086?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-42086 published?

CVE-2021-42086 was published on 2021-10-07 and last updated on 2026-06-17.

CVE-2021-42086

CVE-2021-42086 is a high-severity vulnerability in Zammad with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Zammad
Published: 2021-10-07
Last modified: 2026-06-17

Description

An issue was discovered in Zammad before 4.1.1. An Agent account can modify account data, and gain admin access, via a crafted request.

Frequently asked questions

What is CVE-2021-42086?: An issue was discovered in Zammad before 4.1.1. An Agent account can modify account data, and gain admin access, via a crafted request.
How severe is CVE-2021-42086?: CVE-2021-42086 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-42086 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42086?: CVE-2021-42086 affects Zammad. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42086?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-42086 published?: CVE-2021-42086 was published on 2021-10-07 and last updated on 2026-06-17.

References

https://zammad.com/en/advisories/zaa-2021-09

Affected products (1)

cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:*

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