### Impact 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 (e.g. 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 heatmap chart 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 Note that this only affects users who have explicitly enabled the legacy Prometheus web UI using the `--enable-feature=old-ui` command-line flag. ### Patches https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d ### Workarounds If at all possible, disable the legacy web UI by removing the `--enable-feature=old-ui` command-line flag). If this is not an option, take the following precautions: - 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. ### References - CVE-2019-10215 — prior stored DOM XSS vulnerability in Prometheus query history, fixed in v2.7.2 - CVE-2026-40179 — prior stored DOM XSS vulnerability in Prometheus web UI (hover tooltips and metrics explorer), fixed in v3.11.2
### Impact 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 (e.g. 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 heatmap chart 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 Note that this only affects users who have explicitly enabled the legacy Prometheus web UI using the `--enable-feature=old-ui` command-line flag. ### Patches https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d ### Workarounds If at all possible, disable the legacy web UI by removing the `--enable-feature=old-ui` command-line flag). If this is not an option, take the following precautions: - 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. ### References - CVE-2019-10215 — prior stored DOM XSS vulnerability in Prometheus query history, fixed in v2.7.2 - CVE-2026-40179 — prior stored DOM XSS vulnerability in Prometheus web UI (hover tooltips and metrics explorer), fixed in v3.11.2
Update github.com/prometheus/prometheus to 0.311.3 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanPrometheus vulnerable to stored XSS via crafted histogram bucket label values in the old web UI heatmap display affects github.com/prometheus/prometheus (go). Severity is medium. ### Impact 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 (e.g. 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 heatmap chart 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 Note that this only affects users who have explicitly enabled the legacy Prometheus web UI using the `--enable-feature=old-ui` command-line flag. ### Patches https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d ### Workarounds If at all possible, disable the legacy web UI by removing the `--enable-feature=old-ui` command-line flag). If this is not an option, take the following precautions: - 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. ### References - CVE-2019-10215 — prior stored DOM XSS vulnerability in Prometheus query history, fixed in v2.7.2 - CVE-2026-40179 — prior stored DOM XSS vulnerability in Prometheus web UI (hover tooltips and metrics explorer), fixed in v3.11.2
AI coding agents often install or upgrade packages automatically in go. A medium vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| github.com/prometheus/prometheusgo | <0.311.3 | 0.311.3 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL GuardUpdate github.com/prometheus/prometheus to 0.311.3 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanPrometheus vulnerable to stored XSS via crafted histogram bucket label values in the old web UI heatmap display affects github.com/prometheus/prometheus (go). Severity is medium. ### Impact 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 (e.g. 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 heatmap chart 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 Note that this only affects users who have explicitly enabled the legacy Prometheus web UI using the `--enable-feature=old-ui` command-line flag. ### Patches https://github.com/prometheus/prometheus/commit/38f23b9075ced1de2b82d2dad8b2bebb1ecd5b7d ### Workarounds If at all possible, disable the legacy web UI by removing the `--enable-feature=old-ui` command-line flag). If this is not an option, take the following precautions: - 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. ### References - CVE-2019-10215 — prior stored DOM XSS vulnerability in Prometheus query history, fixed in v2.7.2 - CVE-2026-40179 — prior stored DOM XSS vulnerability in Prometheus web UI (hover tooltips and metrics explorer), fixed in v3.11.2
AI coding agents often install or upgrade packages automatically in go. A medium vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|---|---|
| github.com/prometheus/prometheusgo | <0.311.3 | 0.311.3 |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard