jose2go is vulnerable to a JWT bomb attack through its decode function

HIGH 7.5CVE-2025-63811 · GHSA-9mj6-hxhv-w67j · GO-2025-4123 · Published 12/11/2025 · updated 05/11/2026

In short

CVE-2025-63811 is a HIGH (CVSS 7.5) vulnerability affecting github.com/dvsekhvalnov/jose2go, jose2go (dvsekhvalnov).
Chance of exploitation in the next 30 days (EPSS): 0.28%, higher than 20.2% of all vulnerabilities.
Fix: update to 1.7.0 or later.

Package	Affected versions	Patched versions
github.com/dvsekhvalnov/jose2go Go	`< 1.7.0`	`1.7.0`
jose2go dvsekhvalnov	`≥ 1.5.0, < 1.7.0`	`1.7.0`

Description

An issue was discovered in dvsekhvalnov jose2go 1.5.0 thru 1.7.0 allowing an attacker to cause a Denial-of-Service (DoS) via crafted JSON Web Encryption (JWE) token with an exceptionally high compression ratio.

NVD description

References

nvd.nist.gov/vuln/detail/CVE-2025-63811 · ADVISORY
dvsekhvalnov/jose2go · WEB
dvsekhvalnov/jose2go commit 0a0673d · WEB
dvsekhvalnov/jose2go · PACKAGE
GitHub Advisory GHSA-9mj6-hxhv-w67j · ADVISORY

More vulnerabilities in github.com/dvsekhvalnov/jose2go

See all →

Running one of these products? Scan your site to see whether it exposes a vulnerable version.

Scan my site free