CVE-2022-36087

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 3.2.2 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/grant_types/base.py#L232
• Vulnerable uri_validate functions: https://github.com/oauthlib/oauthlib/blob/2b8a44855a51ad5a5b0c348a08c2564a2e197ea2/oauthlib/uri_validate.py

PoC

is_absolute_uri("http://[:::::::::::::::::::::::::::::::::::::::]/path")

Acknowledgement

Special thanks to Sebastian Chnelik - PyUp.io

Security Fix(es):

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.(CVE-2022-36087)

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.

The fence-agents packages provide a collection of scripts for handling remote power management for cluster devices. They allow failed or unreachable nodes to be forcibly restarted and removed from the cluster.

Security Fix(es):

• python-oauthlib: DoS when attacker provides malicious IPV6 URI (CVE-2022-36087)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

These are all security issues fixed in the python310-oauthlib-3.2.1-1.1 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the python311-oauthlib-3.2.2-5.4 package on the GA media of openSUSE Tumbleweed.

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.

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.