Case Study: Cross-Platform Persistent Logic Bomb 🛡️

I am currently investigating a unique logic vulnerability that bridges the gap between desktop environments and mobile applications. This report was recently Triaged by Riot Games Security, and I am collaborating with their engineering teams for remediation.

High-Level Overview

The vulnerability involves an Input Validation Failure within a widely-used social metadata synchronization endpoint. By sending a specifically malformed payload, an account can be forced into an "irrecoverable" state across multiple platforms.

The "Logic Bomb" Mechanics

Self-Persistence: The malformed data is stored server-side, meaning a local "fix" (like reinstalling or clearing cache) is ineffective.
Cross-Platform Impact: A payload sent via a desktop-level API successfully "bricks" functionality on the mobile version of the application.
Support-Level Lockdown: The exploit disables the very UI components a standard user would need to revert the changes, necessitating manual intervention from Player Support staff.

Current Investigation Status

Note on Responsible Disclosure: Per standard security protocols and the Riot Games Bug Bounty guidelines, full technical details, endpoints, and Proof-of-Concept (PoC) code are strictly redacted until a patch is confirmed and the report is officially resolved.

Timeline

Discovery: November 2025
Initial Report: December 2025
Research Update: January 2026 (Confirmed persistence in latest live builds)
Status: Triaged (Internal Review)

Why This Matters

While often categorized as "Self-DoS," this vulnerability represents a significant Operational Risk. If weaponized by third-party "Grey Market" software, it could be used as a "Troll Tool" to mass-brick account social features, creating an immense volume of Player Support tickets and manual labor costs.

What's Next?

I am working closely with the Riot Security team to verify the incoming fix. Once the vulnerability has been patched and I receive official permission for disclosure, I will publish a Full Technical Deep-Dive here, including:

The Python automation script used for the PoC.
The specific XMPP/API logic that allowed the payload to bypass local checks.
Lessons learned regarding cross-platform metadata sanitization.

Stay tuned for the full disclosure. For now, we're keeping the details under lock and key to ensure player safety.

Keep the ecosystem safe, and keep hunting! 👊