Integer Overflow in HAProxy 2.0 through 2.5 Allows HTTP Request Smuggling

CVE-2021-40346 · HIGH Severity

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.

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