CVE-2026-77341

Summary

cpp-httplib is a C++ header-only HTTP/HTTPS library. In version 0.49.0, the chunked-response trailer output path writes trailer header names and values directly to the socket without validating them, allowing CRLF sequences in a trailer field to inject additional headers or split the HTTP response. Unlike every other header-writing path in the library, the trailer-writing code applies none of the field-name and field-value checks that reject carriage return and line feed, so an application that places attacker-influenced data into a chunked response trailer emits attacker-controlled CRLF onto the wire. This enables HTTP response splitting, letting an attacker forge response headers or inject a second response. This issue is fixed in version 0.50.0.

Affected Software

VendorProductVersion RangeStatus
yhirosecpp-httplib>= 0.49.0, < 0.50.0affected

Weaknesses

  • CWE-93: CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')
  • CWE-113: CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

References