Php nrk predis: From version 3.0.0-RC1 until version 3.3.0, pipeline handling on aggregate cluster and replication connections reparses an already serialized RESP… (CVE-2026-84372)

Php nrk predis is a PHP client for Redis and Valkey. From version 3.0.0-RC1 until 3.3.0, the pipeline handling on aggregate cluster and replication connections reparses an already serialized RESP buffer incorrectly by splitting it with explode("\r\n") rather than honoring RESP length prefixes. This improper parsing allows attacker-controlled keys or values containing CRLF sequences to be interpreted by Command::deserializeCommand() as additional commands. On cluster connections, the ClusterStrategy::getFakeKey() method can route injected keyless commands using the literal fake key "key", enabling operations such as shard-wide cache deletion, targeted data modification, data reads, or node disruption. On replication connections, malformed reparsing can cause uncaught exceptions that repeatedly terminate affected requests. Only the pipeline() method is vulnerable; transaction() and MULTI are unaffected. The vulnerability is resolved in version 3.3.0.

An attacker can inject additional commands via specially crafted keys or values containing CRLF sequences in pipeline requests. This can lead to unauthorized operations including shard-wide cache deletion, data modification, data reads, or disruption of nodes in a Redis cluster. On replication connections, the vulnerability can cause service instability through repeated request termination due to uncaught exceptions. The CVSS score of 9.8 indicates critical impact on confidentiality, integrity, and availability.

Upgrade php-nrk-predis to version 3.3.0 or later, where this vulnerability is fixed. No other mitigation is indicated or required as the issue is resolved in the official fix.