CVE-2021-29622 | Arbitrary redirects under /new endpoint

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.

Published: 2021-05-19 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-29622 is rated Moderate Risk (61.6/100): CVSS Medium severity, with high exploitation likelihood (EPSS 87.48%, 99th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-29622

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-31 86.66% 87.48% +0.81%
2 2026-04-12 87.36% 86.66% -0.70%
3 2026-04-10 — 87.36% —

Full EPSS history (51 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-29622

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 3.6 [email protected]
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]
5.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 4.9 [email protected]

Weakness enumeration for CVE-2021-29622

GitHub Security Advisory for CVE-2021-29622

GHSA-vx57-7f4q-fpc7 · Severity: medium · Ecosystem: go — Arbitrary redirects under /new endpoint

OS Trackers for CVE-2021-29622

vendor priority summary link
alpine medium CVE-2021-29622: 1 source package rows (prometheus); 7 state rows across 7 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 7, open 0. https://security.alpinelinux.org/vuln/CVE-2021-29622
debian unimportant CVE-2021-29622 unimportant priority: Debian including 1 source packages (prometheus), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-29622
redhat medium — https://access.redhat.com/security/cve/CVE-2021-29622
ubuntu medium CVE-2021-29622 medium priority: Ubuntu including 1 source packages (prometheus), 16 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 14, DNE 1, needed 1. https://ubuntu.com/security/CVE-2021-29622

Affected software / configurations for CVE-2021-29622

Vendor Product Version Raw CPE
prometheus prometheus >= 2.23.0, < 2.26.1 cpe:2.3:a:prometheus:prometheus:*:*:*:*:*:*:*:*
prometheus prometheus 2.27.0 cpe:2.3:a:prometheus:prometheus:2.27.0:-:*:*:*:*:*:*
prometheus prometheus 2.27.0 cpe:2.3:a:prometheus:prometheus:2.27.0:rc0:*:*:*:*:*:*

References for CVE-2021-29622

cvelogic Threat Intelligence