CVE-2026-116566
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk18th percentile - higher than 18% of all known CVEs
Summary
The socket.getaddrinfo() function accepted null bytes within the *host* and *port* parameters, which could cause the values to be silently truncated. This may lead to unintended name resolution or connections to a different address than intended.
Risk Assessment
Silent truncation of host or port values may result in connections to unexpected addresses or ports, potentially bypassing validation and causing misrouting. This may affect communication security.
Recommendation
Update the Python environment to a version containing the fix. Validate input passed to socket.getaddrinfo() for null bytes.
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Original NVD description (English source)
socket.getaddrinfo() previously accepted null bytes within *host* and *port* parameters which can cause the values to be silently truncated.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

