How severe is CVE-2021-39172?

CVE-2021-39172 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-2021-39172 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39172?

CVE-2021-39172 affects Catchethq Catchet. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-39172?

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-2021-39172 published?

CVE-2021-39172 was published on 2021-08-27 and last updated on 2026-06-17.

CVE-2021-39172

CVE-2021-39172 is a high-severity vulnerability in Catchethq Catchet with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 29% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-93.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 29% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-93
Affected product: Catchethq Catchet
Published: 2021-08-27
Last modified: 2026-06-17

Description

Cachet is an open source status page system. Prior to version 2.5.1, authenticated users, regardless of their privileges (User or Admin), can exploit a new line injection in the configuration edition feature (e.g. mail settings) and gain arbitrary code execution on the server. This issue was addressed in version 2.5.1 by improving `UpdateConfigCommandHandler` and preventing the use of new lines characters in new configuration values. As a workaround, only allow trusted source IP addresses to access to the administration dashboard.

Frequently asked questions

What is CVE-2021-39172?: Cachet is an open source status page system. Prior to version 2.5.1, authenticated users, regardless of their privileges (User or Admin), can exploit a new line injection in the configuration edition feature (e.g. mail settings) and gain arbitrary code execution on the server. This issue was addressed in version 2.5.1 by improving `UpdateConfigCommandHandler` and preventing the use of new lines characters in new configuration values. As a workaround, only allow trusted source IP addresses to access to the administration dashboard.
How severe is CVE-2021-39172?: CVE-2021-39172 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-2021-39172 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39172?: CVE-2021-39172 affects Catchethq Catchet. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-39172?: 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-2021-39172 published?: CVE-2021-39172 was published on 2021-08-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:catchethq:catchet:*:*:*:*:*:*:*:*

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