CVE-2026-56818

Netty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, the RedisArrayAggregator Redis codec clears retained partial aggregate state when the maxNestedArrayDepth limit is exceeded, but it does not clear the same state when the sibling maxElements limit is exceeded. A peer can start a valid RESP array, send a bulk string child, then send a nested array header longer than the configured maxElements. Netty throws a decoder exception in decodeRedisArrayHeader, but the existing partial aggregate remains retained in the handler. If the application leaves the channel alive after the exception, later messages are still consumed into the pre-error aggregate, allowing an unauthenticated peer to keep attacker-controlled aggregate state alive across a security-limit exception and pin retained pooled buffers. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b
https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6
https://github.com/netty/netty/pull/17065
https://github.com/netty/netty/security/advisories/GHSA-p9jm-q85p-7mcp
https://github.com/netty/netty/security/advisories/GHSA-p9jm-q85p-7mcp

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-07 18:17

Updated : 2026-09-10 20:43

NVD link : CVE-2026-56818

Mitre link : CVE-2026-56818

CVE.ORG link : CVE-2026-56818

JSON object : View

Products Affected

No product.

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

CWE-703

Improper Check or Handling of Exceptional Conditions

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