Vulnerability Description
Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting') vulnerability in hackney_http_connect in benoitc hackney allows HTTP Request Splitting via the value a proxy_auth_fun callback returns. After a 407 response from an HTTP CONNECT proxy, hackney_http_connect:handle_proxy_auth/11 calls the caller's proxy_auth_fun with the status code and the response headers and writes the returned binary into the Proxy-Authorization line of the CONNECT retry without checking it. A CR, LF or NUL byte in that value adds header lines to the request sent to the proxy. The value is attacker-influenced when the callback derives it from untrusted data, for example from the proxy's challenge headers. Other caller-supplied values on the CONNECT path, such as the target host and the request headers, were already checked for control bytes. This issue affects hackney: from 2.0.0 before 4.9.0.
Related Weaknesses (CWE)
References
- https://cna.erlef.org/cves/CVE-2026-112880.html
- https://github.com/benoitc/hackney/commit/5df5a74a2817d5b12880d217db33253ff1fae1
- https://github.com/benoitc/hackney/commit/5ee7d7d19eba27e774667d472feb1e93a08af7
- https://github.com/benoitc/hackney/pull/989
- https://github.com/benoitc/hackney/releases/tag/4.9.0
- https://osv.dev/vulnerability/EEF-CVE-2026-112880
FAQ
What is CVE-2026-112880?
CVE-2026-112880 is a documented vulnerability. Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting') vulnerability in hackney_http_connect in benoitc hackney allows HTTP Request Splitting via the value a pro...
How severe is CVE-2026-112880?
CVSS scoring is not yet available for CVE-2026-112880. Check NVD for updates.
Is there a patch for CVE-2026-112880?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.