REDHAT-BUG-2294682: Low severity pypi/cpython vulnerability
CPython 3.9 and earlier doesn't disallow configuring an empty list ("[]") for SSLContext.setnpnprotocols() which is an invalid value for the underlying OpenSSL API. This results in a buffer over-read when NPN is used (see CVE-2024-5535 for OpenSSL). This vulnerability is of low severity due to NPN being not widely used and specifying an empty list likely being uncommon in-practice (typically a protocol name would be configured).
https://github.com/python/cpython/commit/39258d3595300bc7b952854c915f63ae2d4b9c3e https://github.com/python/cpython/pull/23014 https://jbp.io/2024/06/27/cve-2024-5535-openssl-memory-safety.html https://mail.python.org/archives/list/security-announce@python.org/thread/PLP2JI3PJY33YG6P5BZYSSNU66HASXBQ/
Affected Software
Event History
Frequently Asked Questions
What is the severity of REDHAT-BUG-2294682?
The severity of REDHAT-BUG-2294682 is considered low.
How do I fix REDHAT-BUG-2294682?
To fix REDHAT-BUG-2294682, ensure that an empty list is not configured for SSLContext.set_npn_protocols() in CPython 3.9 or earlier.
What is the impact of REDHAT-BUG-2294682?
The impact of REDHAT-BUG-2294682 includes a potential buffer over-read when NPN is used.
Which versions of CPython are affected by REDHAT-BUG-2294682?
CPython versions up to and including 3.9 are affected by REDHAT-BUG-2294682.
Is the NPN protocol related to REDHAT-BUG-2294682 vulnerable?
Yes, the NPN protocol is related to REDHAT-BUG-2294682 and can lead to vulnerabilities when improperly configured.