[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$f1csps5t51tzsa":3},{"success":4,"breach":5},true,{"_id":6,"name":7,"title":8,"slug":7,"domain":9,"breachDate":10,"addedDate":11,"modifiedDate":12,"contentUpdatedAt":13,"source":14,"sourceUrl":15,"sourceUrls":16,"pwnCount":19,"affectedCount":19,"affectedCountStatus":20,"affectedCountLowerBound":21,"affectedCountUnit":22,"hasEnglishDescription":4,"severity":23,"dataClasses":24,"description":29,"seoTitle":30,"seoTitleEn":31,"seoDescription":30,"seoDescriptionEn":32,"logoUrl":33,"isVerified":4,"isSensitive":34,"isSpamList":34,"isMalware":34,"company":35},"68e3266eda11adda4882519d","dueling-network","Dueling Network Data Breach","duelingnetwork.com","2017-03-29T00:00:00.000Z","2020-03-30T00:44:49.000Z","2026-07-02T12:26:55.059Z","2026-07-18T23:50:03.717Z","Database leak","https:\u002F\u002Fwww.vice.com\u002Fen\u002Farticle\u002Fhacker-steals-millions-of-accounts-from-yu-gi-oh-fan-project-dueling-network\u002F",[15,17,18],"https:\u002F\u002Fwww.bitdefender.com\u002Fen-us\u002Fblog\u002Fhotforsecurity\u002Fhacker-steals-6-5-million-accounts-from-yu-gi-oh-clone","https:\u002F\u002Fwww.twingate.com\u002Fblog\u002Ftips\u002Fdueling-network-data-breach",6486626,"known",null,"unknown","Critical",[25,26,27,28],"Email addresses","IP addresses","Passwords","Usernames","\u003Cp>The Dueling Network data breach is a high-risk credential leak that affected online card game and forum accounts. In the incident dated March 29, 2017, it was confirmed that user data associated with 6,486,626 records fell into unauthorized hands. Although the main game service of Dueling Network closed in 2016, the forum section remained open for a while, causing old account data to continue posing a risk. Therefore, the incident should not be seen solely as an old game account issue; if the same email address, username, or password was used in other accounts, its impact can continue even years later.\u003C\u002Fp>\n\u003Cp>The verified data classes are email addresses, IP addresses, usernames, and password hashes stored using the MD5 algorithm. MD5 is a fast hashing method considered weak for modern password storage standards; attackers can attempt to crack such hashes more easily with offline trial lists. This does not mean that the password has been published in plain text for everyone, but it significantly increases the risk of account compromise for individuals using the same or similar passwords across different services.\u003C\u002Fp>\n\u003Ch2>Leaked Data Types and Risks\u003C\u002Fh2>\n\u003Cp>The most critical element in the Dueling Network record is the password data. Even if passwords are stored in MD5 hash form, breaking the hash can become practical for weak or reused passwords. A password hash found along with a username and email address provides an attacker with a strong starting point for credential stuffing attempts. In particular, if the same password has been used for a game, forum, email, social media, or payment account, a single old forum leak can turn into a much broader account security issue.\u003C\u002Fp>\n\u003Cp>IP addresses alone are not definitive proof of identity; however, when evaluated together with the account name and email, they can provide insights into the user's regional connection information, service provider clues, or previous session patterns. Usernames are also important because players may use the same nickname across different games, streams, forums, or social platforms. This matching makes targeted phishing messages more convincing and sets the stage for social engineering attempts on new accounts by leveraging the history of old accounts.\u003C\u002Fp>\n\u003Ch2>Verified Scope and Boundaries\u003C\u002Fh2>\n\u003Cp>The verified scope for this record is 6,486,626 account registrations. This number should not be read as the one-to-one count of unique individuals; there may be multiple accounts belonging to the same person, inactive accounts, or duplicate records, especially in older forum environments. Therefore, the correct way to describe it is that account data related to millions of players and forum users has been exposed. The date of the incident should be considered March 29, 2017, and subsequent verification or archiving dates should not be presented as the date the breach occurred.\u003C\u002Fp>\n\u003Cp>The verified data fields are email address, IP address, password hash, and username. Additional fields in the record such as full name, phone number, physical address, payment card, in-game purchase history, or private message content are not part of the verified data class. This boundary must be specifically maintained in the text, because exaggerated descriptions about old game and forum accounts can mislead the user. Safe evaluation should focus on the risk of identity information and account matching.\u003C\u002Fp>\n\u003Ch2>User Groups at Risk\u003C\u002Fh2>\n\u003Cp>The highest risk group consists of people who reuse the password from their Dueling Network account elsewhere. Passwords used in old game forums may often have been reused on email, social media, streaming, shopping, or other gaming platforms. In this case, an attacker may attempt to take over accounts by trying leaked email and username combinations on different services. Even if the password hash is not cracked, the username and email match can provide enough context for targeted phishing messages.\u003C\u002Fp>\n\u003Cp>The second risk group consists of people who have used the same username across different communities for many years. When a gamer tag, forum nickname, and email address are seen together, a person's different online profiles can be linked. When the IP address is added to this picture, attackers may try to make inferences about the user's location, connection habits, or service provider clues. The risk is greater for users registered with a corporate email address because an old game account can serve as a seemingly trustworthy context in phishing attempts targeting the work account.\u003C\u002Fp>\n\u003Ch2>Urgent Measures to Be Taken\u003C\u002Fh2>\n\u003Cp>If the password used on the Dueling Network account has been repeated on any other account, it should be changed immediately. The priority should be email accounts, social media, game stores, accounts linked to payments, and forum profiles created with the same username. New passwords should be unique, long, and random; simply adding a number or symbol to the end of the old password should not be considered sufficient. Using a password manager makes it easier to generate different and strong passwords for each service.\u003C\u002Fp>\n\u003Cp>If two-step verification is supported on accounts, it should be enabled. The email account should be particularly protected, because password reset links for many services are sent to email. The user should be careful about login links, password reset alerts, and account verification messages that come under the pretext of Dueling Network or old game accounts. Old forum accounts registered with the same email address should also be reviewed, unused accounts should be closed, or their passwords should be changed.\u003C\u002Fp>\n\u003Ch2>Long-Term Security Strategies\u003C\u002Fh2>\n\u003Cp>This incident shows that even accounts on closed or unused services can have a security impact. Users should regularly review their old registrations, close forum and game accounts they no longer use, or at least isolate them with unique passwords. Using the same email address in many communities for years makes it easier to link profiles when a leak occurs. Therefore, using separate email aliases for different purposes reduces risk in the long term.\u003C\u002Fp>\n\u003Cp>On the corporate side, employees' use of work email on personal forums and gaming accounts should be restricted. Username, email, and password hash combinations from old leaks can be used in automated attempts against corporate login systems. Security teams should consider such old breaches not only as historical records but also as a risk indicator that measures password reuse and employee awareness. Since the impact of passwords stored with weak hash algorithms can persist for a long time, password reset and multi-factor authentication policies should be kept up to date.\u003C\u002Fp>\n\u003Ch2>Record Control and User Action\u003C\u002Fh2>\n\u003Cp>If your email address appears in this record, first consider the passwords you used during the same period as Dueling Network and change all accounts where the same password was used. Even if the old service is closed, the same credentials might work on other accounts. Check for unknown logins, forwarding rules, and password reset messages in your email account. If you used the same username on gaming communities, streaming platforms, and forums, also review the login history and security settings on those accounts.\u003C\u002Fp>\n\u003Cp>The correct user action for this breach is to eliminate the reuse of credentials without panicking. The leaked data does not verify fields such as payment cards or physical addresses; however, the combination of email, username, IP address, and weakly hashed password is sufficiently serious for account security. Make your passwords unique, enable two-factor authentication, do not click on suspicious messages, and regularly close old accounts. These steps significantly reduce the risk of the Dueling Network-related threat spreading to other accounts.\u003C\u002Fp>","","Dueling Network Data Breach (6.5 Million Reported Records)","Dueling Network Data Breach. 6.5 Million reported records were reported. Reported data: Email addresses, IP addresses, Passwords. Review the scope, risks, and…","\u002Fuploads\u002Flogo\u002Fduelingnetwork_com.webp",false,{"name":36,"sector":37,"country":38,"website":9,"websiteArchiveUrl":30,"websiteStatus":30,"websiteCheckedAt":21},"Dueling Network","Gaming","United States"]