VYPR
← All advisories
Medium severity5.3NVD Advisory· Published Aug 25, 2023· Updated Jun 17, 2026

CVE-2023-40217

CVE-2023-40217

Description

An issue was discovered in Python before 3.8.18, 3.9.x before 3.9.18, 3.10.x before 3.10.13, and 3.11.x before 3.11.5. It primarily affects servers (such as HTTP servers) that use TLS client authentication. If a TLS server-side socket is created, receives data into the socket buffer, and then is closed quickly, there is a brief window where the SSLSocket instance will detect the socket as "not connected" and won't initiate a handshake, but buffered data will still be readable from the socket buffer. This data will not be authenticated if the server-side TLS peer is expecting client certificate authentication, and is indistinguishable from valid TLS stream data. Data is limited in size to the amount that will fit in the buffer. (The TLS connection cannot directly be used for data exfiltration because the vulnerable code path requires that the connection be closed on initialization of the SSLSocket.)

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

299

Patches

Vulnerability mechanics

References

7

News mentions

0

No linked articles in our index yet.