Stored XSS in Alertmanager

1) Stored cross-site scripting

EUVDB-ID: #VU79967

Risk: Low

CVSSv3.1: 4.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-40577

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data passed to the /api/v1/alerts endpoint in the Alertmanager UI. A remote user can inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

alertmanager: 0.0.1 - 0.25.0

External links

http://github.com/prometheus/alertmanager/releases/tag/v0.26.0
http://github.com/prometheus/alertmanager/releases/tag/v0.25.1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.