CVE-2020-5300

Disallow replay of `private_key_jwt` by blacklisting JTIs in Hydra

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

Category

5.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: ory hydra
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2020-5300?
CVE-2020-5300 has been scored as a medium severity vulnerability.
How to fix CVE-2020-5300?
To fix CVE-2020-5300, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-5300 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-5300 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-5300?
CVE-2020-5300 affects ory hydra.
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