Description

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR & LF characters in user supplied headers, allowing untrusted header value to escape header lines. This vulnerability allows attackers to add extra headers, modify request body unexpectedly & trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue.

INFO

Published Date :

2026-01-01T17:54:43.959Z

Last Modified :

2026-01-02T18:50:20.380Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-21428 vulnerability.

Vendors Products
Yhirose
  • Cpp-httplib
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-21428.

URL Resource
https://github.com/yhirose/cpp-httplib/commit/98048a033a532ff22320ce1d11789f8d5710dfcd cve-icon cve-icon cve-icon
https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0 cve-icon cve-icon cve-icon
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-wpc6-j37r-jcx7 cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-21428 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-21428 cve-icon
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CVSS Vulnerability Scoring System

Detailed values of each vector for above chart.
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Detailed values of each vector for above chart.
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User Interaction
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Integrity Impact
Availability Impact