23 Oct 2026 15:48:27 UTC
Http4s: Ember chunk parser lenience (TE.TE request smuggling)
cve-program · CVE-2026-69216 · Published
CVE-2026-69216
Http4s: Ember chunk parser lenience (TE.TE request smuggling)
CVSS 3.1 5.4 MEDIUMCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-69216
PublishedHttp4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s chunk decoder trims the chunk-size token and accepts leading plus or minus signs instead of requiring one or more hexadecimal digits followed by the required CRLF. When an intermediary forwards chunked data without re-encoding and interprets malformed chunk boundaries differently, an unauthenticated attacker can create TE.TE request smuggling that bypasses intermediary controls, poisons caches, or hijacks the request queue. The same response-path leniency can enable response smuggling against an ember-client used as a gateway when the upstream is malicious or compromised. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
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