CVE-2020-26116: http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 al...

Security readout for executives and security teams

Some Python versions allowed a malicious value used as the HTTP method to insert line breaks into an outgoing HTTP request. Business risk depends on whether applications let external users influence that method. This is not a broad remote takeover issue by itself, but it can corrupt requests or affect downstream HTTP handling in exposed services. Exposure is likely limited to applications running affected Python versions that use http.client and let untrusted input choose the HTTP method. Standard fixed-method clients are less likely exposed. Asset owners should also check distributor advisories because Fedora, Ubuntu, Debian, Gentoo, openSUSE, Oracle, and NetApp published related notices. Treat as a targeted dependency remediation item, not an emergency by default. Prioritize systems where user input can influence outbound HTTP requests, especially internet-facing automation, proxies, integrations, or security-sensitive internal services. Mitigation focus: Upgrade Python to fixed upstream versions or vendor-supported patched packages.; Prioritize internet-facing services that make outbound HTTP requests from user-controlled workflows.; Reject CR, LF, and unexpected method values before calling HTTP client libraries..

Prepared

Jun 5, 2026, 14:11 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.