CVE-2023-40577

Alertmanager UI is vulnerable to stored XSS via the /api/v1/alerts endpoint

Description

Alertmanager handles alerts sent by client applications such as the Prometheus server. An attacker with the permission to perform POST requests on the /api/v1/alerts endpoint could be able to execute arbitrary JavaScript code on the users of Prometheus Alertmanager. This issue has been fixed in Alertmanager version 0.2.51.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 1.48% Top 20%
Vendor Advisory github.com
Affected: prometheus alertmanager
Published at:
Updated at:

References

Link Tags
https://github.com/prometheus/alertmanager/security/advisories/GHSA-v86x-5fm3-5p7j vendor advisory
https://lists.debian.org/debian-lts-announce/2023/10/msg00011.html mailing list

Frequently Asked Questions

What is the severity of CVE-2023-40577?
CVE-2023-40577 has been scored as a high severity vulnerability.
How to fix CVE-2023-40577?
To fix CVE-2023-40577, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-40577 being actively exploited in the wild?
It is possible that CVE-2023-40577 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-40577?
CVE-2023-40577 affects prometheus alertmanager.
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