Medium severity · published May 19, 2021
CVE-2021-29622
Prometheus is an open-source monitoring system and time series database
6.1
CVSS
19.6%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)19.6% · higher than 97% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PR
Prometheus · Prometheus
2.23.0 before 2.26.1; 2.27.0; 2.27.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-29622
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-29622
Third Party Advisory
https://github.com/prometheus/prometheus/releases/tag/v2.26.1
Third Party Advisory
https://github.com/prometheus/prometheus/releases/tag/v2.27.1
Third Party Advisory
https://github.com/prometheus/prometheus/security/advisories/GHSA-vx57-7f4q-fpc7
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