CVE-2026-77341 (GCVE-0-2026-77341)

Vulnerability from cvelistv5 – Published: 2026-08-27 22:16 – Updated: 2026-08-28 15:30
VLAI
Title
cpp-httplib: CRLF injection via unvalidated HTTP trailer headers in chunked response writing
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.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 15:29 UTC
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
  • CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
yhirose cpp-httplib Affected: >= 0.49.0, < 0.50.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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