Vulnerability in Golang-Jwt Jwt
CVE-2025-30204
golang-jwt is a Go implementation of JSON Web Tokens. Starting in version 3.2.0 and prior to versions 5.2.2 and 4.5.2, the function parse.ParseUnverified splits (via a call to 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. This issue is fixed in 5.2.2 and 4.5.2.
EPSS: 0.007 (51.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Golang-jwt Jwt — versions >= 3.2.0, < 4.5.2, >= 5.0.0-rc.1, < 5.2.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2025-30204?
- CVE-2025-30204 is a high-severity vulnerability in Golang-Jwt Jwt, classified under Asymmetric Resource Consumption (Amplification). CVSS score: 7.5/10. Published 2025-03-21.
- How severe is CVE-2025-30204?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-30204 known to be exploited?
- 6 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.