Vulnerability · Published Mar 13, 2026 · Assigned by GitHub_M
CVE-2026-32627cpp-httplib has a Silent TLS Certificate Verification Bypass on HTTPS Redirect via Proxy
High 8.7
In plain English
A high-severity improper certificate validation in cpp-httplib from yhirose. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | cpp-httplib | no fix listed | DEBIAN-CVE-2026-32627 |
| Debian:13 | cpp-httplib | no fix listed | DEBIAN-CVE-2026-32627 |
| Debian:14 | cpp-httplib | 0.41.0+ds-3 | DEBIAN-CVE-2026-32627 |
| Ubuntu:25.10 | cpp-httplib | no fix listed | UBUNTU-CVE-2026-32627 |
| Ubuntu:26.10 | cpp-httplib | no fix listed | UBUNTU-CVE-2026-32627 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| yhirose | cpp-httplib | < 0.37.2 |
Weakness: CWE-295 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
References
- https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-c3h8-fqq4-xm4g x_refsource_CONFIRM