Open Redirect in Prometheus

CVE-2021-29622

Prometheus is an open-source monitoring system and time series database. In 2.23.0, Prometheus changed its default UI to the New ui. To ensure a seamless transition, the URL's prefixed by /new redirect to /. Due to a bug in the code, it is possible for an attacker to craft an URL that can redirect to any other URL, in the /new endpoint. If a user visits a prometheus server with a specially crafted address, they can be redirected to an arbitrary URL. The issue was patched in the 2.26.1 and 2.27.1 releases. In 2.28.0, the /new endpoint will be removed completely. The workaround is to disable access to /new via a reverse proxy in front of Prometheus.

Vulnerability class: Open Redirect

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.196 (97.3th percentile), scored .

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-29622: held from 0.196 to 0.196.

EPSS over last 30 days · oldest: 0.196 · newest: 0.196 · change: 0.000

Affected products

  • Prometheus — versions 2.27.0, >= 2.23.0, < 2.27.1

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-29622?
CVE-2021-29622 is a medium-severity vulnerability in Prometheus, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.5/10. Published 2021-05-19.
How severe is CVE-2021-29622?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-29622 known to be exploited?
10 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.