CVE-2025-30204
jwt-go allows excessive memory allocation during header parsing
Impact
### Summary Function [`parse.ParseUnverified`](https://github.com/golang-jwt/jwt/blob/c035977d9e11c351f4c05dfeae193923cbab49ee/parser.go#L138-L139) currently splits (via a call to [strings.Split](https://pkg.go.dev/strings#Split)) its argument (which is untrusted data) on periods. As a result, in the face of a malicious request whose _Authorization_ header consists of `Bearer ` followed by many period characters, a call to that function incurs allocations to the tune of O(n) bytes (where n stands for the length of the function's argument), with a constant factor of about 16. Relevant weakness: [CWE-405: Asymmetric Resource Consumption (Amplification)](https://cwe.mitre.org/data/definitions/405.html) ### Details See [`parse.ParseUnverified`](https://github.com/golang-jwt/jwt/blob/c035977d9e11c351f4c05dfeae193923cbab49ee/parser.go#L138-L139) ### Impact Excessive memory allocation
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/golang-jwt/jwt/v5 | >= 5.0.0-rc.1, < 5.2.2 | 5.2.2 |
| go | github.com/golang-jwt/jwt/v4 | < 4.5.2 | 4.5.2 |
| go | github.com/golang-jwt/jwt | >= 3.2.0, <= 3.2.2 | none recorded |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/golang-jwt/jwt/commit/0951d184286dece21f73c85673fd308786ffe9c3
- https://github.com/golang-jwt/jwt/commit/bf316c48137a1212f8d0af9288cc9ce8e59f1afb
- https://github.com/golang-jwt/jwt/security/advisories/GHSA-mh63-6h87-95cp
- https://security.netapp.com/advisory/ntap-20250404-0002/
- https://github.com/advisories/GHSA-mh63-6h87-95cp
- https://nvd.nist.gov/vuln/detail/CVE-2025-30204
- https://security.netapp.com/advisory/ntap-20250404-0002