CVE-2026-88407

A heap-based out-of-bounds write in the ws_read_frame function (src/bolt/ws.c) and the buffer_apply_mask function (src/bolt/buffer.c) in FalkorDB before 4.20.0 allows a remote unauthenticated attacker to cause a denial of service and possibly corrupt heap memory by sending a WebSocket frame with a 64-bit extended payload length to the Bolt port. The payload length is not bounded, and the only bounds check in buffer_apply_mask is an ASSERT(), which is compiled out in release builds, so the function XORs memory beyond the end of the receive buffer with the attacker-supplied mask key. Only deployments that enable the Bolt endpoint (BOLT_PORT, disabled by default) are affected.

A heap-based out-of-bounds write in the BoltReadHandler function (src/bolt/bolt_api.c) in FalkorDB before 4.20.0 allows a remote unauthenticated attacker to cause a denial of service and possibly execute arbitrary code by sending a Bolt RESET message with an attacker-chosen chunk size to the Bolt port. The handler checks the size only with ASSERT(), which is compiled out in release builds, then computes a destination pointer from the wire-supplied 16-bit size and moves buffered data up to about 64 KiB backwards past the start of the read buffer. Only deployments that enable the Bolt endpoint (BOLT_PORT, disabled by default) are affected.

A vulnerability in FalkorDB before 4.18.4 causes a heap-based out-of-bounds read in the BufferSerializerIOv2_ReadBuffer function. A remote attacker who can issue Redis replication commands (e.g., against an instance with no password) can send a crafted RDB stream with a sub-buffer length field exceeding the remaining buffer size. The only bounds check is an ASSERT(), which is compiled out in release builds, so memcpy() reads past the end of the heap allocation.

A double free and use-after-free vulnerability in the RdbLoadDeletedNodes function of the RDB graph decoders in FalkorDB before 4.18.1. A remote attacker who can issue Redis replication commands can send a crafted RDB stream where the 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.

A type confusion vulnerability in the _read_flags function (src/commands/cmd_dispatcher.c) in FalkorDB before 4.20.0 allows a remote authenticated attacker who can run GRAPH.QUERY to cause a denial of service and possibly disclose or corrupt memory. The function accepts a --bolt argument from any client and casts the following command argument, a Redis string object, to a Bolt client structure without checking its origin; the result-set code then dereferences pointers read from that object. The argument is parsed even when the Bolt endpoint is disabled, so default configurations are affected.

An improper authentication vulnerability in the is_authenticated function (src/bolt/bolt_api.c) in FalkorDB before 4.20.0 allows a remote unauthenticated attacker to execute graph queries without credentials through the Bolt endpoint. The function decides whether a password is required by issuing an empty AUTH command to Redis and treats only a WRONGPASS error as meaning that a password is required; any other error, such as LOADING while a dataset is being loaded, MASTERDOWN during replication failover, or OOM under memory pressure, causes the client to be treated as authenticated. Only deployments that enable the Bolt endpoint (BOLT_PORT, disabled by default) are affected.

A stack-based buffer overflow in the _RdbLoadEntity function of the RDB graph decoders in FalkorDB before 4.18.4. A remote attacker who can issue Redis replication commands can send a crafted RDB stream with an attacker-controlled entity property count. The count sizes two variable-length arrays on the thread stack with no upper bound, and the decoder then fills them with attacker-supplied values.

An integer overflow in the _BulkInsert_ReadProperty component (/bulk_insert.c) of FalkorDB (Redis module) v4.20.1 allows attackers to cause a Denial of Service (DoS) via a crafted input.

Improper error handling in the GRAPH.EFFECT component in FalkorDB (Redis module) v4.20.1 leads to a Denial of Service (DoS) within the application.

The graph.UDF in FalkorDB (Redis module) v4.20.1 to v4.20.4 is not registered as a write command, leading to unexpected behavior within the application.