CVE-2020-5300 Disallow replay of `private_key_jwt` by blacklisting JTIs in Hydra

What is CVE-2020-5300?

CVE-2020-5300 is a medium-severity vulnerability in ory hydra, published on 6 Apr 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

Official description

In Hydra (an OAuth2 Server and OpenID Certified™ OpenID Connect Provider written in Go), before version 1.4.0+oryOS.17, when using client authentication method 'private_key_jwt' [1], OpenId specification says the following about assertion `jti`: "A unique identifier for the token, which can be used to prevent reuse of the token. These tokens MUST only be used once, unless conditions for reuse were negotiated between the parties". Hydra does not check the uniqueness of this `jti` value. Exploiting this vulnerability is somewhat difficult because: - TLS protects against MITM which makes it difficult to intercept valid tokens for replay attacks - The expiry time of the JWT gives only a short window of opportunity where it could be replayed This has been patched in version v1.4.0+oryOS.17

Weakness: CWE-294

Which versions are affected by CVE-2020-5300?

3 open source packages ship an affected version, including github.com/ory/hydra. It affects 1 product.

Products include Ory Hydra.

How do I fix CVE-2020-5300?

Upgrade github.com/ory/hydra to 1.4.0 or later.

Is CVE-2020-5300 being exploited?

There is no known exploitation of CVE-2020-5300 in the wild and no public exploit code.

Other vulnerabilities in ory hydra

• CVE-2026-33504 Ory Hydra has a SQL injection via forged pagination tokens High 7.2
• CVE-2019-8400 Hydra has Reflected XSS via error_hint parameter Medium 6.1

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-3p3g-vpw6-4w66, GO-2022-0786.