Service interruption via unbounded HTTP method labels
Published Feb 15, 2022 · Updated Apr 23, 2025
Resource exhaustion in Prometheus client_golang before 1.11.1 allows remote attackers to interrupt instrumented HTTP services. Affected promhttp InstrumentHandler middleware records each unchecked HTTP method string as a distinct method-label value, creating unbounded metric-series cardinality. Exposure requires a method-labeled metric, no method filtering before the middleware, and no intermediary that rejects unknown methods; repeated unique methods continuously add time series and exhaust memory.
Summary
What happened
Resource exhaustion in Prometheus client_golang before 1.11.1 allows remote attackers to interrupt instrumented HTTP services. Affected promhttp InstrumentHandler middleware records each unchecked HTTP method string as a distinct method-label value, creating unbounded metric-series cardinality. Exposure requires a method-labeled metric, no method filtering before the middleware, and no intermediary that rejects unknown methods; repeated unique methods continuously add time series and exhaust memory.
The record
- CVE
- CVE-2022-21698
- Published
- Feb 15, 2022
- Updated
- Apr 23, 2025
- Vendor
- Prometheus
- Product
- Prometheus client_golang
- Classifications
- CWE-770, CWE-400, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 15, 2022CVE publishedPublication date reported by the CVE source.
- Apr 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 1.11.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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