Service interruption via exponential regex backtracking
Published Jun 1, 2022 · Updated Sep 17, 2024
Regular expression denial of service in semver-regex before 3.1.4 and 4.0.0 through 4.0.2 allows attackers to exhaust CPU. The semverRegex function returns a pattern whose nested repetition over prerelease segments backtracks exponentially on strings containing repeated '-.--' fragments. Reachability requires a consuming application to pass attacker-controlled text to test(); processing consumes excessive CPU and can interrupt that service.
Summary
What happened
Regular expression denial of service in semver-regex before 3.1.4 and 4.0.0 through 4.0.2 allows attackers to exhaust CPU. The semverRegex function returns a pattern whose nested repetition over prerelease segments backtracks exponentially on strings containing repeated '-.--' fragments. Reachability requires a consuming application to pass attacker-controlled text to test(); processing consumes excessive CPU and can interrupt that service.
The record
- CVE
- CVE-2021-43307
- Published
- Jun 1, 2022
- Updated
- Sep 17, 2024
- Vendor
- Sindre Sorhus
- Product
- semver-regex
- Classifications
- CWE-1333, CAPEC-492, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 1, 2022CVE publishedPublication date reported by the CVE source.
- Sep 17, 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=unspecified <3.1.4 changes=[{"at":"4.0.3","status":"unaffected"}]
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- JFrog semver-regex ReDoS proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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