Polygon Discloses Security Flaws Fixed in Recent Hard Forks

{"heading_1":"Details of the Security Flaws","paragraph_1":"Polygon Labs' Validators Support Team disclosed that the vulnerabilities affected the Bor and Heimdall clients, including denial-of-service risks, validator resource exhaustion, and flaws in checkpoint and milestone processing.","paragraph_2":"The most severe issue involved Heimdall, where a specially crafted transaction could force validators to perform excessive processing work, potentially disrupting the network.","paragraph_3":"The Austin hard fork separately addressed two denial-of-service risks in Bor that could have slowed block processing or caused nodes to crash.","paragraph_4":"Polygon stated that the flaws were fixed through the Austin and Kyoto hard forks, which were deployed privately and tested before being activated on mainnet and publicly disclosed.","paragraph_5":"Nodes running older versions of either client past the hard fork activation heights have already fallen out of consensus and must upgrade to rejoin the canonical network.","paragraph_6":"Bor v2.10.0 is required for all Polygon PoS nodes, while Heimdall v0.11.0 is required for validators and full nodes, with both upgrades already active on mainnet."}