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{"bugzilla": {"description": "haproxy: HAProxy: HTTP Request Smuggling via HTTP/3 Multiplexer Desynchronization", "id": "2532644", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532644"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L", "status": "draft"}, "cwe": "CWE-444", "details": ["A flaw was found in HAProxy. A remote, unauthenticated attacker can exploit a vulnerability in the HTTP/3 multiplexer when processing requests without a Content-Length header, leading to HTTP request smuggling. This occurs when HAProxy is configured with QUIC support and an HTTP/3 frontend, and traffic is routed to a backend over HTTP/1.1 using chunked transfer coding on a reused connection. Successful exploitation allows the attacker to bypass frontend security rules and potentially intercept or cause the loss of other clients' requests, including sensitive information like authentication credentials."], "name": "CVE-2026-90678", "package_state": [{"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "haproxy", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-09-13T03:37:55Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-90678\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-90678\nhttp://git.haproxy.org/?p=haproxy.git;a=commit;h=86a4ebc761a278838e8cb06f3a292282ba704c65\nhttps://github.com/haproxy/haproxy/commit/86a4ebc761a278838e8cb06f3a292282ba704c65\nhttps://www.haproxy.org/download/3.5/src/CHANGELOG"], "threat_severity": "Important"}