Medium 6.1Published May 26, 2026

CVE-2026-44903Prometheus is an open-source monitoring system and time series database.

Updated under an hour ago (2026-10-19 10:10 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for prometheus

Exploited in the last 30 days

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: 6.1 MEDIUM (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-79
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jul 24, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

prometheus prometheus prometheus:prometheus	from 2.49.0 before 3.5.3; from 3.6.0 before 3.11.3	NVD

References

https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7dpatch
https://github.com/prometheus/prometheus/security/advisories/GHSA-fw8g-cg8f-9j28mitigation, patch, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.