cve.bz

CVE-2026-44903

5.1 mediumEPSS 0.2%

Medium (5.1) in prometheus prometheus. EPSS 0.2% chance of exploitation in the next 30 days. Fixed in github.com/prometheus/prometheus 0.311.3.

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.

Severity

CVSS 4.0

5.1 medium
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

CVSS 3.1

6.1 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.2% chance of exploitation in the next 30 days; higher than 10% of CVEs (scores of 2026-10-31)
CWE
CWE-79
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-fw8g-cg8f-9j28Gogithub.com/prometheus/prometheus<0.311.30.311.3
GO-2026-5381Gogithub.com/prometheus/prometheus<0.311.30.311.3

References

Check your stackJSON