{"investigation":{"slug":"cysic","entity_name":"Cysic","trust_score":35,"severity_base":null,"score_modifier":0,"confidence":0.75,"status":"published","content_type":"investigation","summary":"Cysic is a zero-knowledge proof hardware-acceleration project and Layer 1 network, founded in 2022 and backed by a $6 million seed round led by Polychain Capital. On October 17, 2026, Cysic's cross-chain bridge connecting its native chain to BNB Smart Chain and Base was exploited: an attacker gained unauthorized access to a database supporting the bridge and exploited a flaw in its message-processing logic to mint 10 million unauthorized CYS tokens, of which roughly 7.2 million were sold for about $727,000 in ETH before the receiving address was blacklisted 76 minutes later.","sections":[{"content":"On October 17, 2026, an attacker minted 10 million unauthorized CYS tokens on BNB Smart Chain by exploiting Cysic's cross-chain bridge. The Cysic Foundation stated that the attacker 'gained unauthorized access to a database used by services supporting the bridge' and separately exploited a flaw in the bridge's message-processing logic to submit a fraudulent mint message. According to The Block's reconstruction of the on-chain transactions, the attacker sold approximately 5.65 million CYS for 588,315 USDT within minutes of the mint, routed funds through a SWFT BridgersSwap contract and Mayan Finance to acquire ETH on Ethereum, and sold a further 1.55 million CYS for roughly 220 BNB, which was likewise bridged to Ethereum via Mayan and deBridge. In total, about 7.2 million CYS were sold across 26 transfers in 15 transactions, with twelve transactions routed through OKX's DEX aggregator, netting the attacker roughly 306.6 ETH (about $727,000 at the time). Cysic blacklisted the receiving address in the CYS token contract 76 minutes after the initial mint, freezing approximately 2.8 million of the unauthorized tokens; the blacklist applies only to CYS on BNB Chain and does not affect the ETH already obtained. Cysic stated that the incident was confined to the bridge's message-processing and minting functions, that its mainnet was unaffected, and that 'existing user assets were not stolen.' The bridge remained suspended pending a security review by an unnamed third-party firm, and Cysic said the 10-million-token mint figure does not by itself represent the final U.S.-dollar loss.","heading":"October 2026 Bridge Exploit","sources":[{"url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863","name":"Cysic suspends bridge after attacker mints tokens and moves $727,000 to Ethereum","type":"news_article","credibility":2},{"url":"https://coinmarketcap.com/academy/article/cysic-bridge-exploit-10-million-cys-unauthorized-minting","name":"Cysic Bridge Exploit Leads to Unauthorized Minting of 10M CYS Tokens","type":"news_article","credibility":2},{"url":"https://cryptobriefing.com/cysic-halts-bridge-unauthorized-cys-mint/","name":"Cysic halts crypto bridge after unauthorized mint of 10M CYS","type":"news_article","credibility":2},{"url":"https://cointelegraph.com/news/cysic-crypto-bridge-halted-after-unauthorized-mint-of-10m-cys","name":"Cointelegraph: Cysic crypto bridge halted after unauthorized mint of 10M CYS","type":"news_article","credibility":2}],"severity":"high"},{"content":"Following the exploit, Cysic announced plans to burn 7.2 million CYS from its foundation reserves by the end of October 2026 to offset the amount sold by the attacker and to restore alignment with its original tokenomics model. The unauthorized mint represented roughly 1% of circulating supply at the time, and reporting described circulating supply rising by approximately 6.22% as a result of the mint before remediation. No source reviewed describes a compensation or reimbursement plan for users or liquidity providers affected by the incident, and Cysic had not published a promised follow-up report detailing verified losses or fund-tracing progress as of the most recent sources reviewed.","heading":"Remediation and Token Supply Impact","sources":[{"url":"https://phemex.com/news/article/cysic-plans-to-burn-72-million-cys-by-end-of-october-after-crosschain-bridge-security-incident-100799","name":"Cysic plans to burn 7.2 million CYS by end of October after cross-chain bridge security incident","type":"news_article","credibility":2},{"url":"https://cryptoticker.io/de/cysic-bridge-unautorisierter-mint/","name":"Cysic stoppt die Bridge: 10 Millionen CYS ohne Deckung, 6,22 Prozent mehr Umlauf","type":"news_article","credibility":2}],"severity":"medium"},{"content":"Cysic is a zero-knowledge proof hardware-acceleration project, founded in 2022, that operates a Layer 1 network and a zkVM called Venus for verifiable computation, alongside a proprietary ASIC chip (C1) intended to accelerate ZK-proof generation. The project raised a $6 million seed round led by Polychain Capital in 2023. Prior to the October 2026 bridge incident, no major prior security incidents or regulatory actions involving Cysic were identified in available reporting.","heading":"Background","sources":[{"url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863","name":"Cysic suspends bridge after attacker mints tokens and moves $727,000 to Ethereum (background section)","type":"news_article","credibility":2}],"severity":"low"}],"timeline":[{"date":"2022","event":"Cysic is founded as a zero-knowledge proof hardware-acceleration project.","source":"The Block","source_url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863"},{"date":"2023","event":"Cysic raises a $6 million seed round led by Polychain Capital.","source":"The Block","source_url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863"},{"date":"2026-10","event":"Attacker exploits Cysic's bridge message-processing logic to mint 10 million unauthorized CYS tokens on BNB Smart Chain.","source":"The Block","source_url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863","date_evidence":"8:31 a.m.: The attacker minted 10 million unauthorized CYS on BNB Chain.","date_original":"2026-10-17"},{"date":"2026-10","event":"Cysic blacklists the attacker's receiving address on the CYS token contract, freezing about 2.8 million CYS, 76 minutes after the initial mint.","source":"The Block","source_url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863","date_evidence":"9:47 a.m.: Cysic blacklisted the address in the CYS token contract, 76 minutes after the exploit","date_original":"2026-10-17"},{"date":"2026-10","event":"Cysic publicly confirms the bridge suspension and provides preliminary findings citing unauthorized database access and a message-processing flaw.","source":"The Block","source_url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863","date_original":"2026-10-18"},{"date":"2026-10","event":"Cysic announces plans to burn 7.2 million CYS from foundation reserves by the end of October 2026 to offset the unauthorized mint.","source":"Phemex","source_url":"https://phemex.com/news/article/cysic-plans-to-burn-72-million-cys-by-end-of-october-after-crosschain-bridge-security-incident-100799"}],"sources_used":[{"url":"https://theblock.co/news/defi/2026-10-18-cysic-suspends-bridge-after-attacker-mints-tokens-and-moves-727000-to-ethereum-418863","name":"Cysic suspends bridge after attacker mints tokens and moves $727,000 to Ethereum","type":"news_article","credibility":2},{"url":"https://coinmarketcap.com/academy/article/cysic-bridge-exploit-10-million-cys-unauthorized-minting","name":"Cysic Bridge Exploit Leads to Unauthorized Minting of 10M CYS Tokens","type":"news_article","credibility":2},{"url":"https://cryptobriefing.com/cysic-halts-bridge-unauthorized-cys-mint/","name":"Cysic halts crypto bridge after unauthorized mint of 10M CYS","type":"news_article","credibility":2},{"url":"https://cointelegraph.com/news/cysic-crypto-bridge-halted-after-unauthorized-mint-of-10m-cys","name":"Cointelegraph: Cysic crypto bridge halted after unauthorized mint of 10M CYS","type":"news_article","credibility":2},{"url":"https://phemex.com/news/article/cysic-plans-to-burn-72-million-cys-by-end-of-october-after-crosschain-bridge-security-incident-100799","name":"Cysic plans to burn 7.2 million CYS by end of October after cross-chain bridge security incident","type":"news_article","credibility":2},{"url":"https://cryptoticker.io/de/cysic-bridge-unautorisierter-mint/","name":"Cysic stoppt die Bridge: 10 Millionen CYS ohne Deckung, 6,22 Prozent mehr Umlauf","type":"news_article","credibility":2}],"source_tags":[],"addresses":[],"reviewed":false,"reviewed_by":null,"model_used":"claude-code-investigator","created_at":"2026-11-04T12:28:54.396936+00:00","updated_at":"2026-11-04T12:28:59.921+00:00"},"source_quality":{"total":6,"tier1":0,"tier2":2,"tier3":0,"unrated":4},"follower_count":null,"content_updated_at":"2026-11-04T12:28:54.750Z","last_fact_checked_at":null,"fact_check_next_allowed_at":null,"update_next_allowed_at":null}