CVE-2026-32627

HIGH

cpp-httplib has a Silent TLS Certificate Verification Bypass on HTTPS Redirect via Proxy

Title source: cna
STIX 2.1

Description

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.37.2, when a cpp-httplib client is configured with a proxy and set_follow_location(true), any HTTPS redirect it follows will have TLS certificate and hostname verification silently disabled on the new connection. The client will accept any certificate presented by the redirect target — expired, self-signed, or forged — without raising an error or notifying the application. A network attacker in a position to return a redirect response can fully intercept the follow-up HTTPS connection, including any credentials or session tokens in flight. This vulnerability is fixed in 0.37.2.

Scores

CVSS v3 8.7
EPSS 0.0003
EPSS Percentile 9.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-295
Status published
Products (1)
yhirose/cpp-httplib < 0.37.2 (2 CPE variants)
Published Mar 16, 2026
Tracked Since Mar 16, 2026