lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing. This behavior can be exploited to conduct HTTP Header Smuggling attacks.
Successful exploitation may allow an attacker to:
This issue affects lighttpd1.4.80
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This behavior can be exploited to conduct HTTP Header Smuggling attacks.\n\nSuccessful exploitation may allow an attacker to:\n\n * Bypass access control rules\n * Inject unsafe input into backend logic that trusts request headers\n * Execute HTTP Request Smuggling attacks under some conditions\n\n\nThis issue affects lighttpd1.4.80","Type":"Description","Title":"HTTP Header Smuggling via Trailer Merge"}]}}}