CVE-2026-34441
cpp-httplib: HTTP Request Smuggling via Unconsumed GET Request Body
- State
- Published
- Severity
- 4.8 Medium
- Published
- Mar 31, 2026
- Updated
- Apr 1, 2026
- Reserved
- Mar 27, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.8 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N | GitHub_M |
Weaknesses
- CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Affected Products
| Product | Versions |
|---|---|
cpp-httplibyhirose |
|
References
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