Prometheus up to 3.5.2/3.11.2 cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability was found in Prometheus up to 3.5.2/3.11.2. It has been declared as problematic. This affects an unknown function. The manipulation results in cross site scripting. This vulnerability was named CVE-2026-44903. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Prometheus up to 3.5.2/3.11.2. Affected is some unknown processing. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

Prometheus is an open-source monitoring system and time series database. From 2.49.0 to before 3.5.3 and 3.11.3, in the Prometheus server's legacy web UI (enabled via the command-line flag --enable-feature=old-ui), the histogram heatmap chart view does not escape le label values when inserting them into the HTML for use as axis tick mark labels. An attacker who can inject crafted metrics can execute JavaScript in the browser of any Prometheus user who views the metric in the heatmap chart UI. This vulnerability is fixed in 3.5.3 and 3.11.3.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-44903 since 05/07/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 3.5.3 or 3.11.3 eliminates this vulnerability. Applying the patch 38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1292). Once again VulDB remains the best source for vulnerability data.

Affected

  • Red Hat Enterprise Linux
  • SUSE Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Microsoft Azure Linux
  • Open Source Prometheus
  • Red Hat OpenShift

Productinfo

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Prometheus 3.5.3/3.11.3
Patch: 38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d

Timelineinfo

05/07/2026 CVE reserved
05/27/2026 +20 days Advisory disclosed
05/27/2026 +0 days VulDB entry created
07/14/2026 +48 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-fw8g-cg8f-9j28
Status: Confirmed

CVE: CVE-2026-44903 (🔒)
GCVE (CVE): GCVE-0-2026-44903
GCVE (VulDB): GCVE-100-365868
CERT Bund: WID-SEC-2026-1292 - Prometheus: Mehrere Schwachstellen

Entryinfo

Created: 05/27/2026 06:37
Updated: 07/14/2026 17:08
Changes: 05/27/2026 06:37 (68), 06/06/2026 22:27 (11), 07/14/2026 17:08 (7)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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