Vulnerability-Lookup

GHSA-VFFH-X6R8-XX99

Vulnerability from github – Published: 2026-04-13 16:39 – Updated: 2026-04-16 21:56

Summary

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

Details

Impact

Stored cross-site scripting (XSS) via crafted metric names in the Prometheus web UI:

Old React UI + New Mantine UI: When a user hovers over a chart tooltip on the Graph page, metric names containing HTML/JavaScript are injected into innerHTML without escaping, causing arbitrary script execution in the user's browser.
Old React UI only: When a user opens the Metric Explorer (globe icon next to the PromQL expression input field), and a metric name containing HTML/JavaScript is rendered in the fuzzy search results, it is injected into innerHTML without escaping, causing arbitrary script execution in the user's browser.
Old React UI only: When a user views a heatmap chart and hovers over a cell, the le label values of the underlying histogram buckets are interpolated into innerHTML without escaping. While le is conventionally a numeric bucket boundary, Prometheus does not enforce this — arbitrary UTF-8 strings are accepted as label values, allowing script injection via a crafted scrape target or remote write.

With Prometheus v3.x defaulting to UTF-8 metric and label name validation, characters like <, >, and " are now valid in metric names and labels, making this exploitable.

An attacker who can inject metrics (via a compromised scrape target, remote write, or OTLP receiver endpoint) can execute JavaScript in the browser of any Prometheus user who views the metric in the Graph UI. From the XSS context, an attacker could for example:

Read /api/v1/status/config to extract sensitive configuration (although credentials / secrets are redacted by the server)
Call /-/quit to shut down Prometheus (only if --web.enable-lifecycle is set)
Call /api/v1/admin/tsdb/delete_series to delete data (only if --web.enable-admin-api is set)
Exfiltrate metric data to an external server

Both the new Mantine UI and the old React UI are affected. The vulnerable code paths are:

web/ui/mantine-ui/src/pages/query/uPlotChartHelpers.ts — tooltip innerHTML with unescaped labels.__name__
web/ui/react-app/src/pages/graph/GraphHelpers.ts — tooltip content with unescaped labels.__name__
web/ui/react-app/src/pages/graph/MetricsExplorer.tsx — fuzzy search results rendered via dangerouslySetInnerHTML without sanitization
web/ui/react-app/src/vendor/flot/jquery.flot.heatmap.js — heatmap tooltip with unescaped label values

Patches

A patch has been published in Prometheus 3.5.2 LTS and Prometheus 3.11.2. The fix applies escapeHTML() to all user-controlled values (metric names and label values) before inserting them into innerHTML. This advisory will be updated with the patched version once released.

Workarounds

If using the remote write receiver (--web.enable-remote-write-receiver), ensure it is not exposed to untrusted sources.
If using the OTLP receiver (--web.enable-otlp-receiver), ensure it is not exposed to untrusted sources.
Ensure scrape targets are trusted and not under attacker control.
Do not enable admin / mutating API endpoints (e.g. --web.enable-admin-api or web.enable-lifecycle) in cases where you cannot prevent untrusted data from being ingested.
Users should avoid clicking untrusted links, especially those containing functions such as label_replace, as they may generate poisoned label names and values.

Acknowledgements

Thanks to @gladiator9797 (Duc Anh Nguyen from TinyxLab) for reporting this.

Severity ?

5.3 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/prometheus/prometheus"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "last_affected": "3.5.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/prometheus/prometheus"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.6.0"
            },
            {
              "last_affected": "3.11.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/prometheus/prometheus"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.311.2-0.20260410083055-07c6232d159b"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40179"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-13T16:39:16Z",
    "nvd_published_at": "2026-04-15T23:16:09Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nStored cross-site scripting (XSS) via crafted metric names in the Prometheus web UI:\n\n* **Old React UI + New Mantine UI:** When a user hovers over a chart tooltip on the Graph page, metric names containing HTML/JavaScript are injected into `innerHTML` without escaping, causing arbitrary script execution in the user\u0027s browser.\n* **Old React UI only:** When a user opens the Metric Explorer (globe icon next to the PromQL expression input field), and a metric name containing HTML/JavaScript is rendered in the fuzzy search results, it is injected into `innerHTML` without escaping, causing arbitrary script execution in the user\u0027s browser.\n* **Old React UI only:** When a user views a heatmap chart and hovers over a cell, the `le` label values of the underlying histogram buckets are interpolated into `innerHTML` without escaping. While `le` is conventionally a numeric bucket boundary, Prometheus does not enforce this \u2014 arbitrary UTF-8 strings are accepted as label values, allowing script injection via a crafted scrape target or remote write.\n\nWith Prometheus v3.x defaulting to UTF-8 metric and label name validation, characters like `\u003c`, `\u003e`, and `\"` are now valid in metric names and labels, making this exploitable.\n\nAn attacker who can inject metrics (via a compromised scrape target, remote write, or OTLP receiver endpoint) can execute JavaScript in the browser of any Prometheus user who views the metric in the Graph UI. From the XSS context, an attacker could for example:\n\n- Read `/api/v1/status/config` to extract sensitive configuration (although credentials / secrets are redacted by the server)\n- Call `/-/quit` to shut down Prometheus (only if `--web.enable-lifecycle` is set)\n- Call `/api/v1/admin/tsdb/delete_series` to delete data (only if `--web.enable-admin-api` is set)\n- Exfiltrate metric data to an external server\n\nBoth the new Mantine UI and the old React UI are affected. The vulnerable code paths are:\n\n- `web/ui/mantine-ui/src/pages/query/uPlotChartHelpers.ts` \u2014 tooltip `innerHTML` with unescaped `labels.__name__`\n- `web/ui/react-app/src/pages/graph/GraphHelpers.ts` \u2014 tooltip content with unescaped `labels.__name__`\n- `web/ui/react-app/src/pages/graph/MetricsExplorer.tsx` \u2014 fuzzy search results rendered via `dangerouslySetInnerHTML` without sanitization\n- `web/ui/react-app/src/vendor/flot/jquery.flot.heatmap.js` \u2014 heatmap tooltip with unescaped label values\n\n### Patches\n\nA patch has been published in Prometheus 3.5.2 LTS and Prometheus 3.11.2. The fix applies `escapeHTML()` to all user-controlled values (metric names and label values) before inserting them into `innerHTML`. This advisory will be updated with the patched version once released.\n\n### Workarounds\n\n- If using the remote write receiver (`--web.enable-remote-write-receiver`), ensure it is not exposed to untrusted sources.\n- If using the OTLP receiver (`--web.enable-otlp-receiver`), ensure it is not exposed to untrusted sources.\n- Ensure scrape targets are trusted and not under attacker control.\n- Do not enable admin / mutating API endpoints (e.g. `--web.enable-admin-api` or `web.enable-lifecycle`) in cases where you cannot prevent untrusted data from being ingested.\n- Users should avoid clicking untrusted links, especially those containing functions such as label_replace, as they may generate poisoned label names and values.\n\n### Acknowledgements\n\nThanks to @gladiator9797 (Duc Anh Nguyen from TinyxLab) for reporting this.",
  "id": "GHSA-vffh-x6r8-xx99",
  "modified": "2026-04-16T21:56:19Z",
  "published": "2026-04-13T16:39:16Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/prometheus/prometheus/security/advisories/GHSA-vffh-x6r8-xx99"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40179"
    },
    {
      "type": "WEB",
      "url": "https://github.com/prometheus/prometheus/pull/18506"
    },
    {
      "type": "WEB",
      "url": "https://github.com/prometheus/prometheus/commit/07c6232d159bfb474a077788be184d87adcfac3c"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/prometheus/prometheus"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Prometheus has Stored XSS via metric names and label values in Prometheus web UI tooltips and metrics explorer"
}

CVE-2026-40179 (GCVE-0-2026-40179)

Vulnerability from cvelistv5 – Published: 2026-04-15 22:26 – Updated: 2026-04-16 14:21

Title

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

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.

Severity ?

5.3 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

GitHub_M

References

URL

Tags

	https://github.com/prometheus/prometheus/security…	x_refsource_CONFIRM
	https://github.com/prometheus/prometheus/pull/18506	x_refsource_MISC
	https://github.com/prometheus/prometheus/commit/0…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	prometheus	prometheus	Affected: >= 3.0.0, < 3.5.2 Affected: >= 3.6.0, < 3.11.2 Affected: < 0.311.2-0.20260410083055-07c6232d159b

Show details on NVD website