CVE-2026-103866CWE-436CWE-444

CVE-2026-103866: vulnerability in Apache Sling Engine

Apache Sling Engine: Hand-rolled parameter parser diverges from RFC/container parsing, enabling smuggling

Published

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3Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackepss 0.2%
Inconsistent interpretation of HTTP requests ('HTTP Request/Response smuggling') vulnerability in Apache Sling Engine. The engine's query/form parser accepts non-standard percent-escapes, wrong charsets, and continues request processing on such errors. This issue affects Apache Sling Engine: before 3.0.4. Users are recommended to upgrade to version 3.0.4, which fixes the issue.
Affected products
Apache Software Foundation · Apache Sling Engine
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