Search criteria
1 vulnerability by Keats
CVE-2026-25537 (GCVE-0-2026-25537)
Vulnerability from cvelistv5 – Published: 2026-02-04 21:31 – Updated: 2026-02-05 20:52
VLAI?
Title
jsonwebtoken has Type Confusion that leads to potential authorization bypass
Summary
jsonwebtoken is a JWT lib in rust. Prior to version 10.3.0, there is a Type Confusion vulnerability in jsonwebtoken, specifically, in its claim validation logic. When a standard claim (such as nbf or exp) is provided with an incorrect JSON type (Like a String instead of a Number), the library’s internal parsing mechanism marks the claim as “FailedToParse”. Crucially, the validation logic treats this “FailedToParse” state identically to “NotPresent”. This means that if a check is enabled (like: validate_nbf = true), but the claim is not explicitly marked as required in required_spec_claims, the library will skip the validation check entirely for the malformed claim, treating it as if it were not there. This allows attackers to bypass critical time-based security restrictions (like “Not Before” checks) and commit potential authentication and authorization bypasses. This issue has been patched in version 10.3.0.
Severity ?
CWE
- CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Assigner
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Keats | jsonwebtoken |
Affected:
< 10.3.0
|
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