CVE-2026-103930

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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

14 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 19:17

Updated : 2026-10-16 20:04

NVD link : CVE-2026-103930

Mitre link : CVE-2026-103930

CVE.ORG link : CVE-2026-103930

JSON object : View

Products Affected

No product.

CWE

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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