SwiftNIO HTTP/2 (pre1.45.0) allows HTTP/1.1 request smuggling via control chars
CVE-2026-64785 Published on July 23, 2026
SwiftNIO HTTP/2 was missing validation on inbound HEADERS frames that let CR, LF, NUL, SP and other control characters reach an HTTP/1.1 backend through NIOHTTP2's HTTP/2-to-HTTP/1 codec, enabling HTTP request smuggling or response splitting. This vulnerability is addressed in swift-nio-http2 version 1.45.0.
Products Associated with CVE-2026-64785
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Affected Versions
Apple swift-nio-http2:- Before 1.45.0 is affected.