PT-2026-60794 · Jberger · Mojo::Jwt
CVE-2026-9537
·
Published
2026-07-17
·
Updated
2026-07-17
None
No severity ratings or metrics are available. When they are, we'll update the corresponding info on the page.
Mojo::JWT versions before 1.02 for Perl verify HMAC signatures with a non-constant-time string comparison.
The decode() method compares the supplied signature to the recomputed HMAC with Perl's eq operator, which stops at the first differing byte, so the comparison time varies with the number of matching leading bytes.
A caller that decodes attacker supplied tokens leaks the expected signature through this timing variation, which can be aggregated over many requests to recover the signature and forge a token.
Found an issue in the description? Have something to add? Feel free to write us 👾
Weakness Enumeration
Related Identifiers
Affected Products
Mojo::Jwt