CVE-2026-103930

Impact

cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.

Affected packages

This record carries no package version data, so it cannot be matched against a dependency list automatically. Read the advisory and compare your version by hand.

Weakness classification

References

• NVD record
• CVE.org record
• https://github.com/yhirose/cpp-httplib/commit/255c075b82cf9f221e6e607e8e6789e6e2bf4c2a
• https://github.com/yhirose/cpp-httplib/pull/2501
• https://github.com/yhirose/cpp-httplib/releases/tag/v0.51.0
• https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-vq69-f637-8fhr