【Hacker News搬运】Randar:一个使用LLL格减少破解服务器RNG的Minecraft漏洞
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Title: Randar: A Minecraft exploit that uses LLL lattice reduction to crack server RNG
Randar:一个使用LLL格减少破解服务器RNG的Minecraft漏洞
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Url: https://github.com/spawnmason/randar-explanation/blob/master/README.md
The GitHub repository "randar-explanation" by spawnmason contains a detailed explanation of the Randar exploit, which was discovered in Minecraft versions Beta 1.8 through 1.12.2. The exploit takes advantage of a flaw in Minecraft's code where instances of the `java.util.Random` class are reused insecurely, particularly between generating terrain and in-game actions such as mining blocks. The Randar exploit works by analyzing the precise coordinates of items dropped when blocks are broken. These coordinates can reveal the internal state of the `java.util.Random` class used by the Minecraft server. By using lattice reduction, a method of solving problems in integer programming, the exploit can determine the exact internal state of the random number generator and work backwards to locate other players currently loaded into the world. The exploit was developed for use on the 2b2t Minecraft server, which is known for its "anarchy" ruleset, meaning players are not banned for any reason. On this server, being able to locate other players is a significant advantage, as the only protection players have is the vastness of the map and the fact that others do not know their location. The exploit has been used to locate and loot item stashes belonging to other players, causing significant disruption on the server. The authors of the exploit have also shared a method to patch the vulnerability in Minecraft servers, as well as a tool that allows users to analyze ReplayMod files to find player coordinates. In summary, the Randar exploit is a sophisticated method of exploiting a flaw in Minecraft's random number generation to locate and exploit other players, particularly on servers with anarchy rulesets like 2b2t. The exploit has been well-documented and shared publicly, raising awareness of the vulnerability and the potential for abuse in multiplayer Minecraft gameplay.Post by: leijurv
Comments:
dzdt: Back in 1999-2000 there was an "International RoShamBo Programming Competition" [1] where computer bots competed in the game of rock-paper-scissors. The baseline bot participant just selected its play randomly, which is a theoretically unbeatable strategy. One joke entry to the competition was carefully designed to beat the random baseline ... by reversing the state of the random number generator and then predicting with 100% accuracy what the random player would play.<p>Edit: the random-reversing bot was "Nostradamus" by Tim Dierks, which was declared the winner of the "supermodified" class of programs in the First International RoShamBo Programming Competition. [2]<p>[1] <a href="https://web.archive.org/web/20180719050311/http://webdocs.cs.ualberta.ca/~darse/rsbpc2.html" rel="nofollow">https://web.archive.org/web/20180719050311/http://webdocs.cs...</a>
[2] <a href="https://groups.google.com/g/comp.ai.games/c/qvJqOLOg-oc" rel="nofollow">https://groups.google.com/g/comp.ai.games/c/qvJqOLOg-oc</a>dzdt: 早在1999-2000年；国际RoShamBo编程竞赛”；[1] 计算机机器人在石头剪刀游戏中竞争。基线机器人参与者只是随机选择游戏，这在理论上是不可战胜的策略。比赛中的一个笑话参赛作品是精心设计的，旨在击败随机的底线。。。通过反转随机数生成器的状态，然后100%准确地预测随机玩家将玩什么<p> 编辑：随机反转的机器人是"；诺查丹玛斯"；由Tim Dierks宣布为“；超级修改的“；第一届国际RoShamBo程序设计大赛的程序类。[2] <p>[1]<a href=“https://；/；web.archive.org/：web/！20180719050311&x2F；http://x2F；/；webdocs.cs.ualberta.ca/，~darse/…rsbpc2.html”rel=“nofollow”>https:///；web.archive.org/；web；20180719050311；http://；webdocs.cs</一[2] <a href=“https:/；&x2F；groups.google.comȏ；g/，comp.ai.games/！c/：qvJqOLOg-oc”rel=“nofollow”>https:ȏ/；groups.google.com/；g；comp.ai.games；c；qvJqOLOg oc</a>
chc4: LLL lattice reduction is the same algorithm that can be used for cracking PuTTY keys from biased nonces from the CVE a few days ago. 'tptacek explained a bit about the attack (and links to a cryptopals problem for it, which I can almost pretend to understand if I squint) <a href="https://news.ycombinator.com/item?id=40045377">https://news.ycombinator.com/item?id=40045377</a><p>In a similar vein, the SciCraft minecraft server had a creeper farm which used some sort of black magic setup in order to deterministically manipulate an RNG state to trigger a "random" lightning strike at a specific block every frame in order to get better creeper drops. <a href="https://youtu.be/TM7SutJyDCk" rel="nofollow">https://youtu.be/TM7SutJyDCk</a>
chc4: LLL晶格约简与几天前可用于从CVE的有偏随机数破解PuTTY密钥的算法相同'；tptacek解释了一些关于这次攻击的内容（以及它的cryptopals问题的链接，如果我斜视的话，我几乎可以假装理解）<a href=“https://；/；news.ycombinator.com/！item？id=40045377”>https:///；news.ycombinator.com/；项目id＝40045377</a><p>类似地，SciCraft minecraft服务器有一个爬行农场，它使用某种黑魔法设置来决定性地操纵RNG状态以触发“；“随机”；每帧都会对特定的区块进行雷击，以获得更好的爬行效果<a href=“https://；/；youtu.be/！TM7SutJyDCk”rel=“nofollow”>https:///；youtu.be/；TM7输出DCk</a>
pclmulqdq: I have seen a lot of interesting and funny RNG issues, but this is one of the most sophisticated exploits for the least payout. A wonderful work of art.
pclmulqdq: 我看到了很多有趣的RNG问题，但这是最复杂的漏洞之一，花费最少。一件绝妙的艺术品。
bee_rider: Pretty cool exploit.<p>The idea of a free for all bug abusing server is pretty neat, a whole ‘nother level of the game.<p>I guess this is what “actually fighting” (rather than just using in-game battling mechanics) would look like if the metaverse really happened ever.
bee_rider: 很酷的利用<p> 一个免费的漏洞滥用服务器的想法非常巧妙，是游戏的另一个层次<p> 我想，如果元宇宙真的发生过，这就是“实际战斗”（而不仅仅是使用游戏中的战斗机制）的样子。
ZeWaka: Just watched the video on this! It's definitely a cautionary tale of having your random sources interact - applicable to so many important systems.<p>I often find myself sharing the rng in my code for performance reasons, but stories like this definitely make me pause.
ZeWaka: 刚刚看了这个视频！它；这绝对是一个让你的随机源交互的警示故事——适用于这么多重要的系统<p> 出于性能原因，我经常发现自己在代码中分享rng，但这样的故事肯定会让我停下来。