CVE-2026-103930 (GCVE-0-2026-103930)

Vulnerability from cvelistv5 – Published: 2026-10-14 18:19 – Updated: 2026-10-15 15:06
VLAI
Title
cpp-httplib open_stream serializes CRLF in request target into HTTP request line
Summary
cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-15 13:52 UTC
CWE
  • 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 7751 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
yhirose cpp-httplib Affected: >= 0.29.0, < 0.51.0
guessed Create a notification for this product.
Show details on NVD website
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