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.
{
"severity": "Medium",
"cpes": [
"cpe:2.3:a:prometheus:alertmanager:0.25.0:*:*:*:*:*:*:*",
"cpe:2.3:a:prometheus:alertmanager:*:*:*:*:*:*:*:*"
]
}