How severe is CVE-2017-5621?

CVE-2017-5621 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2017-5621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-5621?

CVE-2017-5621 primarily affects Zammad. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-5621?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-5621 published?

CVE-2017-5621 was published on 2017-03-13 and last updated on 2026-06-17.

CVE-2017-5621

CVE-2017-5621 is a medium-severity vulnerability in Zammad with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Zammad
Published: 2017-03-13
Last modified: 2026-06-17

Description

An issue was discovered in Zammad before 1.0.4, 1.1.x before 1.1.3, and 1.2.x before 1.2.1. XSS can be triggered via malicious HTML in a chat message or the content of a ticket article, when using either the REST API or the WebSocket API.

Frequently asked questions

What is CVE-2017-5621?: An issue was discovered in Zammad before 1.0.4, 1.1.x before 1.1.3, and 1.2.x before 1.2.1. XSS can be triggered via malicious HTML in a chat message or the content of a ticket article, when using either the REST API or the WebSocket API.
How severe is CVE-2017-5621?: CVE-2017-5621 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2017-5621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-5621?: CVE-2017-5621 primarily affects Zammad. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-5621?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-5621 published?: CVE-2017-5621 was published on 2017-03-13 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:*
cpe:2.3:a:zammad:zammad:1.1.0:*:*:*:*:*:*:*
cpe:2.3:a:zammad:zammad:1.1.1:*:*:*:*:*:*:*
cpe:2.3:a:zammad:zammad:1.1.2:*:*:*:*:*:*:*
cpe:2.3:a:zammad:zammad:1.2.0:*:*:*:*:*:*:*

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