CVE-2023-25725

HAProxy before 2.7.3 may allow a bypass of access control because HTTP/1
headers are inadvertently lost in some situations, aka “request smuggling.”
The HTTP header parsers in HAProxy may accept empty header field names,
which could be used to truncate the list of HTTP headers and thus make some
headers disappear after being parsed and processed for HTTP/1.0 and
HTTP/1.1. For HTTP/2 and HTTP/3, the impact is limited because the headers
disappear before being parsed and processed, as if they had not been sent
by the client. The fixed versions are 2.7.3, 2.6.9, 2.5.12, 2.4.22, 2.2.29,
and 2.0.31.