CVE-2026-45372

CRITICAL EPSS 21.1%
Published May 29, 20261mo ago · Modified Jun 17, 20262w ago
9.9 CVSS 3.1
Critical
Find Similar
Published May 29, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.44.0, when cpp-httplib's server parses an incoming request, it applies percent-decoding to every header value except Location and Referer. The validity check (is_field_value) is run before decoding, so encoded %0D%0A passes the check and is then expanded to a literal \r\n byte pair inside the stored header value. This vulnerability is fixed in 0.44.0.

CVSS Details

Base Score
9.9
Exploitability
3.9
Impact
5.3
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Changed
Confidentiality Low
Integrity High
Availability Low

Threat Intelligence

EPSS Exploit Probability
21.1% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 2

CWE-444
CWE-93

Affected Products 1

VendorProductVersionRange
yhirosecpp-httplib* <0.44.0

References 1

  • github.com https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjxg-64p4-vj4m
    ExploitMitigationVendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.