CRLF Injection Affecting cpp-httplib package, versions [,0.30.0)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-CONAN-CPPHTTPLIB-14860882
- published5 Jan 2026
- disclosed1 Jan 2026
- creditHritik V
Introduced: 1 Jan 2026
CVE-2026-21428 (opens in a new tab)How to fix?
Upgrade cpp-httplib to version 0.30.0 or higher.
Overview
Affected versions of this package are vulnerable to CRLF Injection via the processing of untrusted HTTP headers. An attacker can access internal or external network resources by injecting carriage return and line feed characters into user-supplied headers.