CVE-2026-34441

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server's static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive connections, the unread body bytes remain on the TCP stream and are interpreted as the start of a new HTTP request. An attacker can embed an arbitrary HTTP request inside the body of a GET request, which the server processes as a separate request. This issue has been patched in version 0.40.0.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/yhirose/cpp-httplib/releases/tag/v0.40.0	Product Release Notes
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-jv63-rm9j-6jwc	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:yhirose:cpp-httplib:*:*:*:*:*:*:*:*

History

01 Apr 2026, 20:28

Type	Values Removed	Values Added
CPE		cpe:2.3:a:yhirose:cpp-httplib::::::::
First Time		Yhirose cpp-httplib Yhirose
References	~~() https://github.com/yhirose/cpp-httplib/releases/tag/v0.40.0 -~~	() https://github.com/yhirose/cpp-httplib/releases/tag/v0.40.0 - Product, Release Notes
References	~~() https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-jv63-rm9j-6jwc -~~	() https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-jv63-rm9j-6jwc - Exploit, Mitigation, Vendor Advisory

31 Mar 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-31 22:16

Updated : 2026-04-01 20:28

NVD link : CVE-2026-34441

Mitre link : CVE-2026-34441

CVE.ORG link : CVE-2026-34441

JSON object : View

Products Affected

yhirose

cpp-httplib

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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