CVE-2026-77341

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/yhirose/cpp-httplib/commit/568d434e72fc51729d0ad33abffb181e5f7a453d
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-2r2h-jc8w-w66c
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-2r2h-jc8w-w66c

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 00:18

Updated : 2026-09-09 21:09

NVD link : CVE-2026-77341

Mitre link : CVE-2026-77341

CVE.ORG link : CVE-2026-77341

JSON object : View

Products Affected

No product.

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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