# CVE-2026-71646: Robotics-STAR-Lab RACER cooldown bypass denial of service

Source: https://junglewise.ai/threats/cve-2026-71646-robotics-star-lab-racer-cooldown-bypass-denial-of-service  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-11. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-71646 · Severity: high · CVSS 7.5 · Published 2026-09-11

RACER is a swarm robotics exploration framework used to coordinate UAV task optimization. A flaw in the pair-optimization cooldown mechanism allows repeated failed optimization attempts to bypass the intended rate limit and execute at maximum timer frequency, causing excessive CPU consumption, excessive logging, and potential mission degradation on affected UAVs.

Technologies: [Robotics-STAR-Lab (SYSU STAR Group) RACER](https://junglewise.ai/threats/technologies/racer). Vendors: [Robotics-STAR-Lab (SYSU STAR Group)](https://junglewise.ai/threats/vendors/robotics-star-lab-sysu-star-group).

## Quick answers

**Is CVE-2026-71646 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-71646 being exploited in the wild.

**How severe is CVE-2026-71646?** High severity, with a CVSS score of 7.5, published 11 September 2026.

**Which products and versions are affected?** Robotics-STAR-Lab (SYSU STAR Group) RACER commit abcdef1234567890.

**Is there a fix for CVE-2026-71646?** 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-2026-71646 attacked?** It is attacked over the network or from the adjacent network.

**Am I affected by CVE-2026-71646?** Check whether you run Robotics-STAR-Lab (SYSU STAR Group) RACER 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

The vulnerability is a logic flaw in FastExplorationFSM::optTimerCallback() where the cooldown timestamp recent_attempt_time_ is updated only after cost validation succeeds. When a pair-opt reallocation is rejected due to higher cost, the function returns early before updating the timestamp, allowing the same failed operation to bypass the cooldown check on the next timer invocation. An attacker with the ability to trigger or influence pair-opt conditions can cause repeated failed optimization attempts to execute at timer frequency, resulting in denial of service through CPU exhaustion and log flooding. The vulnerability requires local or adjacent network access to the affected UAV's control systems. A fix involves recording the attempt timestamp immediately upon entering optTimerCallback(), before the cost validation, ensuring all attempts—successful, failed, and rejected—are subject to the rate limit.

## Affected products

- Robotics-STAR-Lab (SYSU STAR Group) RACER commit abcdef1234567890

## Timeline

- 2026-09-08: disclosed
- 2026-09-11: advisory

## References

- [https://gist.github.com/DongJiaxin0422/747d8e6c8afc0a364454b741b39bb98c](https://gist.github.com/DongJiaxin0422/747d8e6c8afc0a364454b741b39bb98c)
- [https://github.com/Robotics-STAR-Lab/RACER/issues/51](https://github.com/Robotics-STAR-Lab/RACER/issues/51)

## Related threats

- [RACER denial of service in exploration state machine](https://junglewise.ai/threats/cve-2026-71645-racer-denial-of-service-in-exploration-state-machine)