Polymarket Recovers $164,000 After Private Key Compromise Hit Internal Wallet, Not Core Systems

The core claim — that ZachXBT reported an exploit of the Polymarket UMA CTF Adapter contract on Polygon, with losses rising from over $520,000 to over $660,000 — is strongly corroborated by multiple independent sources published on May 22, 2026. PANews and Odaily (both credible Chinese crypto news outlets) directly cite ZachXBT's Telegram channel as the primary source and confirm the $520,000+ initial figure. BeInCrypto's official X account independently corroborates the $520K figure and the attacker address. The $660,000 upper figure is explicitly cited in the X post by @cryptothedoggy, consistent with the claim's framing of losses escalating over time as the exploit was ongoing. The attacker address (0x8F98075db5d6C620e8D420A8c516E2F2059d9B91) and two affected contract addresses are cited consistently across sources. No source contradicts the claim. The slight uncertainty (0.09 false probability) reflects that the $660K figure is less widely corroborated than $520K, and ZachXBT's original Telegram post could not be directly fetched to verify the exact wording.