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TI-2026-28993 Aliases CVE-2026-40179GHSA-vffh-x6r8-xx99

Prometheus: Stored XSS via metric names and label values in web UI tooltips and metrics explorer

Priority LOW 24CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.

Summary

Prometheus is an open-source monitoring system and time series database. Versions 3.0 through 3.5.1 and 3.6.0 through 3.11.1 have stored cross-site scripting vulnerabilities in multiple components of the Prometheus web UI where metric names and label values are injected into innerHTML without escaping. In both the Mantine UI and old React UI, chart tooltips on the Graph page render metric names containing HTML/JavaScript without sanitization. In the old React UI, the Metric Explorer fuzzy search results use dangerouslySetInnerHTML without escaping, and heatmap cell tooltips interpolate le label values without sanitization. With Prometheus v3.x defaulting to UTF-8 metric and label name validation, characters like <, >, and " are now valid in metric names and labels. An attacker who can inject metrics via a compromised scrape target, remote write, or OTLP receiver endpoint can execute arbitrary JavaScript in the browser of any Prometheus user who views the metric in the Graph UI, potentially enabling configuration exfiltration, data deletion, or Prometheus shutdown depending on enabled flags. This issue has been fixed in versions 3.5.2 and 3.11.2. If developers are unable to immediately update, the following workarounds are recommended: ensure that the remote write receiver (--web.enable-remote-write-receiver) and the OTLP receiver (--web.enable-otlp-receiver) are not exposed to untrusted sources; verify that all scrape targets are trusted and not under attacker control; avoid enabling admin or mutating API endpoints (e.g., --web.enable-admin-api or --web.enable-lifecycle) in environments where untrusted data may be ingested; and refrain from clicking untrusted links, particularly those containing functions such as label_replace, as they may generate poisoned label names and values.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0031 24th percentileScored 2026-11-07
Fix Fixed prometheus (prometheus): 3.5.2, 3.11.2, 0.311.2-0.20260410083055-07c6232d159bgithub.com/prometheus/prometheus (Go): 3.5.2, 3.11.2, 0.311.2-0.20260410083055-07c6232d159b

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
prometheusprometheus3.0.0 to before 3.5.2; 3.6.0 to before 3.11.2; before 0.311.2-0.20260410083055-07c6232d159b3.5.2, 3.11.2, 0.311.2-0.20260410083055-07c6232d159bPatch availableCNA
—github.com/prometheus/prometheus (Go)3.0.0 to before 3.5.23.5.2Patch availableGHSA-vffh-x6r8-xx99
—github.com/prometheus/prometheus (Go)3.6.0 to before 3.11.23.11.2Patch availableGHSA-vffh-x6r8-xx99
—github.com/prometheus/prometheus (Go)before 0.311.2-0.20260410083055-07c6232d159b0.311.2-0.20260410083055-07c6232d159bPatch availableGHSA-vffh-x6r8-xx99
  • prometheus Vendorprometheus Affected 3.0.0 to before 3.5.2; 3.6.0 to before 3.11.2; before 0.311.2-0.20260410083055-07c6232d159b Fixed in 3.5.2, 3.11.2, 0.311.2-0.20260410083055-07c6232d159b Patch available CNA
  • github.com/prometheus/prometheus (Go) Vendor— Affected 3.0.0 to before 3.5.2 Fixed in 3.5.2 Patch available GHSA-vffh-x6r8-xx99
  • github.com/prometheus/prometheus (Go) Vendor— Affected 3.6.0 to before 3.11.2 Fixed in 3.11.2 Patch available GHSA-vffh-x6r8-xx99
  • github.com/prometheus/prometheus (Go) Vendor— Affected before 0.311.2-0.20260410083055-07c6232d159b Fixed in 0.311.2-0.20260410083055-07c6232d159b Patch available GHSA-vffh-x6r8-xx99

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:prometheus:prometheus:*:*:*:*:*:*:*:*3.0.0 to before 3.5.2; 3.6.0 to before 3.11.2Vulnerableprometheus
  • cpe:2.3:a:prometheus:prometheus:*:*:*:*:*:*:*:* Versions 3.0.0 to before 3.5.2; 3.6.0 to before 3.11.2 Vulnerable ·prometheus

Remediation

  • Fix · CNA prometheus (prometheus) Fixed in 3.5.2, 3.11.2, 0.311.2-0.20260410083055-07c6232d159b
  • Fix · GHSA-vffh-x6r8-xx99 github.com/prometheus/prometheus (Go) Fixed in 3.5.2 Advisory →
  • Fix · GHSA-vffh-x6r8-xx99 github.com/prometheus/prometheus (Go) Fixed in 3.11.2 Advisory →
  • Fix · GHSA-vffh-x6r8-xx99 github.com/prometheus/prometheus (Go) Fixed in 0.311.2-0.20260410083055-07c6232d159b Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-40179
  2. 2026-10-03 Alias added: GHSA-vffh-x6r8-xx99
  3. 2026-10-06 Fix available: Go/github.com/prometheus/[email protected], Go/github.com/prometheus/[email protected] · GHSA-vffh-x6r8-xx99

References

Patch 2

Advisory 2

Other 1

  • TI-2021-10330 Arbitrary redirects under /new endpoint CVSS 3.1MEDIUM 6.5
  • TI-2026-30483 Prometheus: remote read endpoint allows denial of service via crafted snappy payload CVSS 3.1HIGH 7.5
  • TI-2026-30481 Prometheus Azure AD remote write OAuth client secret exposed via config API CVSS 3.1HIGH 7.5
  • TI-2019-02838 Cross-site scripting in [UNKNOWN] prometheus CVSS 3.0MEDIUM 6.1
  • TI-2026-32778 Prometheus: Stored XSS via crafted histogram bucket label values in the heatmap display of the old Prometheus web UI CVSS 4.0MEDIUM 5.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences