Unauthenticated denial of service via MIME regex backtracking
Published Jun 11, 2021 · Updated Aug 3, 2024
Uncontrolled resource consumption in Rails Action Pack before 6.0.3.7 and before 6.1.3.2 allows remote attackers to interrupt service. The Action Dispatch MIME type parser applies a backtracking-prone MIME_REGEXP to attacker-controlled Accept header values, causing catastrophic regular-expression backtracking. No authentication or user interaction is required; a crafted HTTP request can monopolize processing resources and interrupt the application service.
Summary
What happened
Uncontrolled resource consumption in Rails Action Pack before 6.0.3.7 and before 6.1.3.2 allows remote attackers to interrupt service. The Action Dispatch MIME type parser applies a backtracking-prone MIME_REGEXP to attacker-controlled Accept header values, causing catastrophic regular-expression backtracking. No authentication or user interaction is required; a crafted HTTP request can monopolize processing resources and interrupt the application service.
The record
- CVE
- CVE-2021-22902
- Published
- Jun 11, 2021
- Updated
- Aug 3, 2024
- Vendor
- Rails
- Product
- Action Pack
- Classifications
- CWE-400, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 11, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record 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=Fixed in 6.0.3.7, 6.1.3.2
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
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Technologies
Your stack
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Your stack
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