CVE-2026-28898: Apple Swiftnio http/2

Medium severity, CVSS 5.3. EPSS: 0.3% chance of exploitation in the next 30 days.

swift-nio-http2's HTTP/2-to-HTTP/1.1 codec did not validate pseudo-header values for control characters before placing them into the translated HTTP/1.1 message. swift-nio-http2 1.44.1 adds validation of all pseudo-header values (:path, :authority, :scheme, :method, and :status) at both the HPACK header validation layer and the HTTP/2-to-HTTP/1.1 translation layer. Requests or responses containing CR, LF, or NUL bytes in any pseudo-header value are now rejected with a connection error. This issue is fixed in swift-nio-http2 1.44.1.

Affected products

• Apple Swiftnio http/2: before 1.44.1 (fixed in 1.44.1)

Published 2026-06-25. Last modified 2026-06-30.