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Ubisoft just spent the tail end of December 2025 in a total defensive crouch. What started as a weird glitch in Tom Clancy’s Rainbow Six Siege turned into a full-blown backend catastrophe that forced the publisher to pull the plug on global servers for over 24 hours.1 This wasn’t a standard “the servers are acting up” situation; this was a fundamental compromise of their internal logic.
The Anatomy of the Breach
The chaos became undeniable on December 27, 2025. Players logging in were greeted with a surreal scene: their accounts were suddenly flush with approximately 2 billion R6 Credits—the game’s premium currency—and virtually every cosmetic item in the game was unlocked. For context, 15,000 credits usually retail for about $100, making the injected value per player essentially infinite.
Beyond the “Christmas come early” vibes, the attackers gained administrative control over the game’s moderation tools. They didn’t stop at credits:
- Automated Chaos: The global ban ticker, usually reserved for catching cheaters, started broadcasting cryptic messages and Shaggy lyrics.
- Account Manipulation: Attackers were actively banning and unbanning players at random, effectively gatekeeping the game from legitimate users.
- Total Shutdown: By 11:00 AM UTC, Ubisoft realized the house was on fire and took Siege and its Marketplace entirely offline to prevent the total collapse of their economy.
The Technical Failure: MongoBleed and Weak APIs
While Ubisoft has been tight-lipped about the exact entry point, security researchers have pointed to a critical vulnerability tracked as CVE-2025-14847, colloquially known as MongoBleed. This exploit allowed threat actors to infiltrate internal databases and Git repositories.
| Vector | Impact |
| CVE-2025-14847 | Deep access to internal source code and database functions. |
| API Vulnerabilities | Broken authentication on endpoints allowed unauthorized administrative calls. |
| Backend Audit | Attackers essentially had the keys to the kingdom, including the ability to gift currency and modify account states. |
The consensus among the technical crowd is that Ubisoft’s backend infrastructure lacked the necessary authorization checks on key API endpoints, allowing the attackers to masquerade as high-level administrators.
The Rollback and Current Status
Ubisoft’s solution was a scorched-earth policy. They initiated a global rollback of all player data to its state before December 27, 10:49 UTC.
- Financial Impact: Every transaction made during the breach window was nuked.While Ubisoft confirmed players wouldn’t be banned for spending the “fake” credits, the items bought with them have been removed.
- The “Two-Week” Recovery: As of December 31, 2025, servers are largely back online, but the Marketplace remains shuttered. Many players are reporting missing legitimate items—collateral damage of the rollback—which Ubisoft claims will take up to two weeks to rectify.
- Infrastructure Stress: Users are still seeing “unplanned issues” on the official status page as the services ramp back up to handle the holiday player load.
The reality here is pretty grim for a triple-A studio. Managing a live-service game for a decade only to have the entire backend subverted by a known database vulnerability suggests a massive gap in their security-aware culture. It’s a reminder that even the biggest players in the industry are often running on legacy systems held together by duct tape and hope.
