CVE-2026-44903

MEDIUM EPSS 8.0%
Published May 26, 20261mo ago · Modified Jun 17, 20262w ago
5.1 CVSS 4.0
Medium
Find Similar
Published May 26, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

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.

CVSS Details

Base Score
5.1
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
8.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-79 Cross-site Scripting Injection

Affected Products 2

VendorProductVersionRange
prometheusprometheus*≥2.49.0  –  <3.5.3
prometheusprometheus*≥3.6.0  –  <3.11.3

References 2

  • github.com https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d
    Patch
  • github.com https://github.com/prometheus/prometheus/security/advisories/GHSA-fw8g-cg8f-9j28
    MitigationPatchVendor Advisory

Remediation

  • github.com https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d
    Patch
  • github.com https://github.com/prometheus/prometheus/security/advisories/GHSA-fw8g-cg8f-9j28
    MitigationPatchVendor Advisory