CVE-2026-88412 Overview
CVE-2026-88412 is an integer overflow vulnerability in FalkorDB v4.20.1, a graph database implemented as a Redis module. The flaw resides in the _BulkInsert_ReadProperty function within /bulk_insert.c. Attackers can send crafted input to the bulk insert interface to trigger the overflow and cause a Denial of Service (DoS) condition. Exploitation requires no authentication and no user interaction over the network. The issue impacts availability of the database process without exposing data confidentiality or integrity.
Critical Impact
An unauthenticated remote attacker can crash or destabilize FalkorDB instances by supplying a malformed bulk insert payload, disrupting graph database services that depend on the module.
Affected Products
- FalkorDB v4.20.1 (Redis module)
- Deployments loading the vulnerable bulk_insert.c component
- Redis servers with the FalkorDB module enabled
Discovery Timeline
- 2026-09-21 - CVE-2026-88412 published to the National Vulnerability Database
- 2026-09-22 - Last updated in NVD database
Technical Details for CVE-2026-88412
Vulnerability Analysis
FalkorDB exposes a bulk insert path that ingests property data during graph load operations. The _BulkInsert_ReadProperty routine in /bulk_insert.c performs arithmetic on attacker-controlled size or length values without adequate bounds validation. When a crafted payload provides values that exceed the storage type's range, the arithmetic wraps around and produces an incorrect result. The module then uses this incorrect value in subsequent memory operations, resulting in a fault that terminates the database process. Because FalkorDB runs inside the Redis server process, the crash removes all graph services hosted by that instance.
Root Cause
The root cause is an integer overflow in the property-reading logic during bulk insert parsing. The function accepts length or count fields from the input stream and uses them in size calculations before validation. Overflowed values pass sanity checks that assume normal arithmetic behavior, leading to invalid memory access or unrecoverable errors downstream.
Attack Vector
An attacker with network access to a Redis instance loading FalkorDB v4.20.1 issues a bulk insert command containing a malformed property field. The overflow triggers during parsing, crashing the process. No credentials or user interaction are required when the Redis endpoint is reachable and accepts commands. Refer to the FalkorDB GitHub Issue #2326 for reproduction details.
Detection Methods for CVE-2026-88412
Indicators of Compromise
- Unexpected Redis or FalkorDB process crashes correlated with GRAPH.BULK or bulk insert commands
- Repeated client reconnections following short-lived bulk insert requests from a single source
- Redis logs containing segmentation faults or assertion failures referencing bulk_insert.c
Detection Strategies
- Inspect Redis command logs for bulk insert operations with abnormally large or malformed property length fields
- Monitor the FalkorDB module for abnormal termination and automatic restart events
- Alert on network traffic patterns targeting Redis ports (default 6379) that precede service outages
Monitoring Recommendations
- Enable Redis MONITOR or slowlog sampling to capture bulk insert payload characteristics
- Forward Redis and container runtime logs to a centralized SIEM for crash correlation
- Track process uptime metrics for the Redis server to detect repeated restarts caused by malformed input
How to Mitigate CVE-2026-88412
Immediate Actions Required
- Restrict network exposure of Redis instances running FalkorDB to trusted application tiers only
- Enforce Redis authentication (requirepass) and TLS to limit access to authorized clients
- Disable or gate the bulk insert interface until a patched FalkorDB release is deployed
Patch Information
No patched version is referenced in the NVD entry at publication time. Monitor the FalkorDB GitHub repository for a fix that adds bounds checks to _BulkInsert_ReadProperty and upgrade once released.
Workarounds
- Place FalkorDB behind a network policy or firewall that blocks untrusted clients from reaching the Redis port
- Use Redis Access Control Lists (ACLs) to deny GRAPH.BULK and related commands for non-administrative users
- Deploy a reverse proxy or command filter that rejects bulk insert payloads with oversized length fields
# Example Redis ACL restricting bulk insert commands
ACL SETUSER appuser on >StrongPasswordHere ~* +@read +@write -GRAPH.BULK
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
