The Varnish Development Team reports:
A client-side desync vulnerability can be triggered in Varnish Cache
and Varnish Enterprise. This vulnerability can be triggered under
specific circumstances involving malformed HTTP/1 requests.
An attacker can abuse a flaw in Varnish's handling of chunked
transfer encoding which allows certain malformed HTTP/1 requests
to exploit improper framing of the message body to smuggle additional
requests. Specifically, Varnish incorrectly permits CRLF to be
skipped to delimit chunk boundaries.
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