Process crash via unchecked prototype-key assignment
Published May 16, 2024 · Updated Feb 13, 2025
Prototype pollution in JWTK nJwt before 0.4.0 allows remote attackers to crash a Node.js process via a crafted JWT. Parser.prototype.parse decodes attacker-controlled header and body properties into JwtHeader and JwtBody objects without rejecting prototype keys such as proto. Reachability requires a consuming application to pass attacker-controlled JWTs to verification, where corrupted prototype methods can terminate the process.
Summary
What happened
Prototype pollution in JWTK nJwt before 0.4.0 allows remote attackers to crash a Node.js process via a crafted JWT. Parser.prototype.parse decodes attacker-controlled header and body properties into JwtHeader and JwtBody objects without rejecting prototype keys such as proto. Reachability requires a consuming application to pass attacker-controlled JWTs to verification, where corrupted prototype methods can terminate the process.
The record
- CVE
- CVE-2024-34273
- Published
- May 16, 2024
- Updated
- Feb 13, 2025
- Vendor
- JWTK
- Product
- nJwt
- Classifications
- CWE-1321
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 16, 2024CVE publishedPublication date reported by the CVE source.
- Feb 13, 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=0 <0.4.0
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
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
- CVE-2024-34273 nJwt prototype-pollution proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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