CVE-2026-5759: Double free and use-after-free in FalkorDB RdbLoadDeletedNodes allows remote code execution via crafted RDB

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-09 · updated 2026-10-13
Weakness: CWE-415

Description

A double free and use-after-free vulnerability in the RdbLoadDeletedNodes function of the RDB graph decoders (src/serializers/decoders/*/decode_graph_entities.c) in FalkorDB before 4.18.1 allows a remote attacker who can issue Redis replication commands (for example, against an instance with no password configured) to cause a denial of service or execute arbitrary code in the redis-server process by supplying a crafted RDB stream whose deleted-nodes buffer length is not a multiple of sizeof(NodeID). The length check relies on ASSERT(), which is compiled out in release builds, so the function continues after freeing the buffer, reading it and freeing it a second time.

Affected products

FalkorDB: before 4.18.1 — fixed in 4.18.1

How to fix

Upgrade to a fixed version: FalkorDB 4.18.1. Check the vendor advisory for mitigations.

References

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