CVE-2026-28434

MEDIUM EPSS 21.7%
Published Mar 4, 20263mo ago · Modified Mar 5, 20263mo ago
5.3 CVSS 3.1
Medium
Find Similar
Published Mar 4, 2026 3mo ago
Last Modified Mar 5, 2026 3mo ago

Description

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, when a request handler throws a C++ exception and the application has not registered a custom exception handler via set_exception_handler(), the library catches the exception and writes its message directly into the HTTP response as a header named EXCEPTION_WHAT. This header is sent to whoever made the request, with no authentication check and no special configuration required to trigger it. The behavior is on by default. A developer who does not know to opt in to set_exception_handler() will ship a server that leaks internal exception messages to any client. This vulnerability is fixed in 0.35.0.

CVSS Details

Base Score
5.3
Exploitability
3.9
Impact
1.4
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Low
Integrity None
Availability None

Threat Intelligence

EPSS Exploit Probability
21.7% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor Information Exposure

Affected Products 1

VendorProductVersionRange
yhirosecpp-httplib* <0.35.0

References 2

  • github.com https://github.com/yhirose/cpp-httplib/commit/defd907c7469c5c8281247b73bbd07be24c31164
    Patch
  • github.com https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-8mpw-r4gc-xm7q
    ExploitMitigationVendor Advisory

Remediation

  • github.com https://github.com/yhirose/cpp-httplib/commit/defd907c7469c5c8281247b73bbd07be24c31164
    Patch