CVE-2026-33745

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-6hrp-7fq9-3qv2	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

01 Apr 2026, 14:44

Type	Values Removed	Values Added
References	~~() https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-6hrp-7fq9-3qv2 -~~	() https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-6hrp-7fq9-3qv2 - Exploit, Mitigation, Vendor Advisory
First Time		Yhirose cpp-httplib Yhirose
CPE		cpe:2.3:a:yhirose:cpp-httplib::::::::
CWE		NVD-CWE-noinfo

30 Mar 2026, 13:26

Type	Values Removed	Values Added
Summary		(es) cpp-httplib es una biblioteca HTTP/HTTPS multiplataforma de un solo archivo y solo de encabezado C++11. Antes de 0.39.0, el cliente HTTP cpp-httplib reenvía las credenciales almacenadas de Basic Auth, Bearer Token y Digest Auth a hosts arbitrarios al seguir redirecciones HTTP de origen cruzado (301/302/307/308). Un servidor malicioso o comprometido puede redirigir al cliente a un host controlado por el atacante, que luego recibe las credenciales en texto plano en el encabezado 'Authorization'. La versión 0.39.0 corrige el problema.

27 Mar 2026, 01:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-27 01:16

Updated : 2026-04-01 14:44

NVD link : CVE-2026-33745

Mitre link : CVE-2026-33745

CVE.ORG link : CVE-2026-33745

JSON object : View

Products Affected

yhirose

cpp-httplib

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

NVD-CWE-noinfo

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