# CVE-2026-88408: FalkorDB stack overflow in _GetGroup function

Source: https://junglewise.ai/threats/cve-2026-88408-falkordb-redis-module-v4-20-1-to-v4-20-4-was-discovered-to  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-21. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-88408 · Severity: medium · CVSS 6.5 · Published 2026-09-21

FalkorDB is a graph database module for Redis used for storing and querying complex data relationships. A stack overflow vulnerability in the query aggregation function allows attackers to crash the database and cause service downtime by sending specially crafted requests. No user data theft or system compromise is possible, but the denial of service could impact business operations relying on FalkorDB availability.

Technologies: [FalkorDB](https://junglewise.ai/threats/technologies/falkordb). Vendors: [FalkorDB](https://junglewise.ai/threats/vendors/falkordb).

## Quick answers

**Is CVE-2026-88408 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-88408 being exploited in the wild.

**How severe is CVE-2026-88408?** Medium severity, with a CVSS score of 6.5, published 21 September 2026.

**Which products and versions are affected?** FalkorDB 4.20.1 to 4.20.4.

**Is there a fix for CVE-2026-88408?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-88408 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-88408?** Check whether you run FalkorDB at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stack overflow exists in the _GetGroup() function in /ops/op_aggregate.c, triggered by unbounded stack variable-length allocation (VLA) sized by the aggregate key_count parameter. The vulnerability is reachable via crafted aggregate query input without authentication. An attacker can trigger a stack exhaustion leading to process crash and denial of service.

## Affected products

- FalkorDB FalkorDB 4.20.1 to 4.20.4

## Timeline

- 2026-09-21: disclosed

## References

- [https://github.com/FalkorDB/FalkorDB/issues/2373](https://github.com/FalkorDB/FalkorDB/issues/2373)

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