Polygon Discloses Vulnerability Details: Multiple Previously Undisclosed Security Flaws Fixed

Polygon disclosed details of multiple previously undisclosed security vulnerabilities fixed in recent Austin and Kyoto hard forks, which could have affected its proof-of-stake network. The vulnerabilities involved Polygon's Bor and Heimdall clients, including denial-of-service risks, validator resource exhaustion, and flaws affecting checkpoint and milestone processing. Polygon stated that fixes were privately tested before deployment to mainnet and public disclosure. The most severe issue involved Heimdall, where specially crafted transactions could force validators to perform excessive processing work, potentially disrupting the network. The Austin hard fork also fixed two denial-of-service risks in Bor that could slow block processing or cause node crashes. Polygon stated that these vulnerabilities were not exploited on mainnet, and fixes were proactively completed before vulnerability details were made public.