User Impersonation Affecting cpp-httplib package, versions [,0.27.0)


Severity

Recommended
0.0
critical
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
0.02% (5th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-CONAN-CPPHTTPLIB-14220403
  • published8 Dec 2025
  • disclosed5 Dec 2025
  • creditnaxus-audit

Introduced: 5 Dec 2025

NewCVE-2025-66570  (opens in a new tab)
CWE-290  (opens in a new tab)

How to fix?

Upgrade cpp-httplib to version 0.27.0 or higher.

Overview

Affected versions of this package are vulnerable to User Impersonation via the read_headers process. An attacker can manipulate server-visible metadata, logging, and authorization decisions by injecting specially crafted HTTP headers that are processed before internal server headers, resulting in the use of attacker-controlled values in downstream code.

References

CVSS Base Scores

version 4.0
version 3.1