CVE-2024-5642
CPython 3.9 and earlier doesn't disallow configuring an empty list ("[]") for SSLContext.set_npn_protocols() which is an invalid value for the underlying OpenSSL API.
Does this matter?
Lower severity and a low EPSS score (0.74%). Track it; it rarely justifies an emergency change on its own.
Description
CPython 3.9 and earlier doesn't disallow configuring an empty list ("[]") for SSLContext.set_npn_protocols() 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).
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
- EPSS
- 0.74% probability · 53th percentile
- CISA KEV
- Not listed
- Source
- cna@python.org
References
- http://www.openwall.com/lists/oss-security/2024/06/28/4
- https://github.com/python/cpython/commit/39258d3595300bc7b952854c915f63ae2d4b9c3e
- https://github.com/python/cpython/commit/a2cdbb6e8188ba9ba8b356b28d91bff60e86fe31
- https://github.com/python/cpython/issues/121227
- 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/
- https://security.netapp.com/advisory/ntap-20240726-0005/
- http://www.openwall.com/lists/oss-security/2024/06/28/4
- https://github.com/python/cpython/commit/39258d3595300bc7b952854c915f63ae2d4b9c3e
- https://github.com/python/cpython/issues/121227
- 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/
- https://security.netapp.com/advisory/ntap-20240726-0005/
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.