HTTP Request Smuggling Affecting org.http4s:http4s-ember-core_2.13 package, versions [,0.23.35)[1.0.0-M1,1.0.0-M47)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JAVA-ORGHTTP4S-19858861
- published16 Sept 2026
- disclosed15 Sept 2026
- creditUnknown
Introduced: 15 Sep 2026
NewCVE-2026-69216 (opens in a new tab)How to fix?
Upgrade org.http4s:http4s-ember-core_2.13 to version 0.23.35, 1.0.0-M47 or higher.
Overview
Affected versions of this package are vulnerable to HTTP Request Smuggling due to lenient parsing in the chunk decoder process. An attacker can bypass intermediary controls, poison caches, or hijack the request queue by crafting specially formatted chunked requests that exploit differences in how intermediaries interpret malformed chunk boundaries. The same leniency can also enable response smuggling when used as a gateway with a malicious or compromised upstream.
Workaround
Users that are not able to upgrade to the fixed version are advised to:
- reject malformed chunk sizes
- buffers and re-encodes request bodies