Headline
Ubuntu Security Notice USN-5632-1
Ubuntu Security Notice 5632-1 - Sebastian Chnelik discovered that OAuthLib incorrectly handled certain redirect uris. A remote attacker could possibly use this issue to cause OAuthLib to crash, resulting in a denial of service.
==========================================================================Ubuntu Security Notice USN-5632-1September 22, 2022python-oauthlib vulnerability==========================================================================A security issue affects these releases of Ubuntu and its derivatives:- Ubuntu 22.04 LTSSummary:OAuthLib could be made to crash if it received specially crafted networktraffic.Software Description:- python-oauthlib: generic, spec-compliant implementation of OAuth for Python3Details:Sebastian Chnelik discovered that OAuthLib incorrectly handled certainredirect uris. A remote attacker could possibly use this issue to causeOAuthLib to crash, resulting in a denial of service.Update instructions:The problem can be corrected by updating your system to the followingpackage versions:Ubuntu 22.04 LTS: python3-oauthlib 3.2.0-1ubuntu0.1In general, a standard system update will make all the necessary changes.References: https://ubuntu.com/security/notices/USN-5632-1 CVE-2022-36087Package Information: https://launchpad.net/ubuntu/+source/python-oauthlib/3.2.0-1ubuntu0.1Related news
### Impact - Attacker providing malicious redirect uri can cause DoS to oauthlib's web application. - Attacker can also leverage usage of `uri_validate` functions depending where it is used. _What kind of vulnerability is it? Who is impacted?_ Oauthlib applications using OAuth2.0 provider support or use directly `uri_validate` function. ### Patches _Has the problem been patched? What versions should users upgrade to?_ Issue fixed in 3.2.1 release. ### Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ The `redirect_uri` can be verified in web toolkit (i.e `bottle-oauthlib`, `django-oauth-toolkit`, ...) before oauthlib is called. A sample check if `:` is present to reject the request can prevent the DoS, assuming no port or IPv6 is fundamentally required. ### References Attack Vector: - Attacker providing malicious redirect uri: https://github.com/oauthlib/oauthlib/blob/d4bafd9f1d0eba3766e933b1ac598cbbf37b8914/oauthlib/oauth2/rfc6749/gran...
OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. In OAuthLib versions 3.1.1 until 3.2.1, an attacker providing malicious redirect uri can cause denial of service. An attacker can also leverage usage of `uri_validate` functions depending where it is used. OAuthLib applications using OAuth2.0 provider support or use directly `uri_validate` are affected by this issue. Version 3.2.1 contains a patch. There are no known workarounds.