CVE-2026-54919

cpp-httplib: TLS certificate chain verification bypassed for IP-literal hosts on Mbed TLS and wolfSSL backends

Published Jul 10, 2026 CVSS 3.1 · 7.4 High EPSS < 1% KEV · Not listed
Description
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In affected Mbed TLS backend versions from 0.31.0 through 0.46.1 and wolfSSL backend versions from 0.33.0 through 0.46.1, when cpp-httplib is built with CPPHTTPLIB_MBEDTLS_SUPPORT or CPPHTTPLIB_WOLFSSL_SUPPORT and a client connects to an IP-literal host with server certificate verification enabled, SSLClient and Client in HTTPS mode skip certificate chain validation and WebSocketClient on the Mbed TLS backend skips verification altogether, allowing a man-in-the-middle attacker positioned to intercept traffic to present a crafted certificate and read or modify the traffic. This issue is fixed in version 0.47.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Yhirose
Yhirose cpp-httplib
Vendors & Products Yhirose
Yhirose cpp-httplib
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In affected Mbed TLS backend versions from 0.31.0 through 0.46.1 and wolfSSL backend versions from 0.33.0 through 0.46.1, when cpp-httplib is built with CPPHTTPLIB_MBEDTLS_SUPPORT or CPPHTTPLIB_WOLFSSL_SUPPORT and a client connects to an IP-literal host with server certificate verification enabled, SSLClient and Client in HTTPS mode skip certificate chain validation and WebSocketClient on the Mbed TLS backend skips verification altogether, allowing a man-in-the-middle attacker positioned to intercept traffic to present a crafted certificate and read or modify the traffic. This issue is fixed in version 0.47.0.
Title cpp-httplib: TLS certificate chain verification bypassed for IP-literal hosts on Mbed TLS and wolfSSL backends
Weaknesses CWE-295
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 14, 2026, 3:55 AM
Reserved
Jun 16, 2026, 1:49 PM
Status
Analyzed
Published
Jul 10, 2026, 5:16 PM
Modified
Oct 25, 2026, 3:10 PM