[OAUTH-WG] JWT: Algorithm choice as an attack vector

Maciej Kwidzinski <mkwidzinski@atlassian.com> Mon, 03 October 2016 15:46 UTC

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From: Maciej Kwidzinski <mkwidzinski@atlassian.com>
Date: Mon, 03 Oct 2016 17:46:36 +0200
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Subject: [OAUTH-WG] JWT: Algorithm choice as an attack vector
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Hi,

Tim McLean describes an attack vector on JWT-protected services in his
blog post: https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/

The culprit is relying on the algorithm in the JWT header. The
workaround/recommendation is to ignore the algorithm from the header
and use a predefined one.

The current RFC 7519 does not address this vulnerability.
Will this problem be addressed in the standard?

Best regards,
Maciej Kwidziński