A critical remote code execution (RCE) vulnerability was discovered in the now-defunct mobile game Marvel: Contest of Champions (also known as Marvel Rivals). The game's chat functionality lacked proper input sanitization, allowing attackers to inject and execute arbitrary JavaScript code within clients of other players. This could have been exploited to steal sensitive information, manipulate game data, or even potentially take control of affected devices. The vulnerability, discovered by a security researcher while reverse-engineering the game, was responsibly disclosed to Kabam, the game's developer. Although a fix was implemented, the exploit served as a stark reminder of the potential security risks associated with unsanitized user inputs in online games.
The post details the reverse engineering process of Call of Duty's anti-cheat driver, specifically version 1.4.2025. The author uses a kernel debugger and various tools to analyze the driver's initialization, communication with the game, and anti-debugging techniques. They uncover how the driver hides itself from process lists, intercepts system calls related to process and thread creation, and likely monitors game memory for cheats. The analysis includes details on specific function calls, data structures, and control flow within the driver, illustrating how it integrates deeply with the operating system kernel to achieve its anti-cheat goals. The author's primary motivation was educational, focusing on the technical aspects of the reverse engineering process itself.
Hacker News users discuss the reverse engineering of Call of Duty's anti-cheat system, Tactical Advantage Client (TAC). Several express admiration for the technical skill involved in the analysis, particularly the unpacking and decryption process. Some question the legality and ethics of reverse engineering anti-cheat software, while others argue it's crucial for understanding its potential privacy implications. There's skepticism about the efficacy of kernel-level anti-cheat and its potential security vulnerabilities. A few users speculate about potential legal ramifications for the researcher and debate the responsibility of anti-cheat developers to be transparent about their software's behavior. Finally, some commenters share anecdotal experiences with TAC and its impact on game performance.
Summary of Comments ( 54 )
https://news.ycombinator.com/item?id=42920962
Hacker News users discussed the exploit detailed in the blog post, focusing on the surprising simplicity of the vulnerability and the potential impact it could have had. Several commenters expressed amazement that such a basic oversight could exist in a production game, with one pointing out the irony of a game about superheroes being vulnerable to such a mundane attack. The discussion also touched on the responsible disclosure process, with users questioning why Kabam hadn't offered a bug bounty and acknowledging the author's ethical handling of the situation. Some users debated the severity of the vulnerability, with opinions ranging from "not a big deal" to a serious security risk given the game's access to user data. The lack of a detailed technical explanation in the blog post was also noted, with some users desiring more information about the specific code involved.
The Hacker News post titled "Remote Code Execution in Marvel Rivals Game" (https://news.ycombinator.com/item?id=42920962) has a moderate number of comments, discussing various aspects of the linked blog post detailing a game exploit. Several commenters focus on the technical details of the exploit, while others discuss the broader implications for game security and the responsible disclosure process.
One compelling comment thread revolves around the surprising simplicity of the vulnerability. Commenters express astonishment that such a basic oversight could exist in a production game, especially given the potential security implications. The discussion touches upon the possibility of this being a common issue in other games and the need for better security practices in game development.
Another interesting thread focuses on the author's decision to withhold certain technical details of the exploit to prevent malicious actors from replicating it. Commenters generally agree with this approach, acknowledging the potential harm that could be caused if the exploit were to become widely known. Some discuss the ethical responsibilities of security researchers in disclosing vulnerabilities and the balance between transparency and protecting users.
Some comments also delve into the specifics of the exploit, questioning the author's description of it as "Remote Code Execution (RCE)." They argue that while the exploit allows for manipulating game data and potentially impacting other players, it doesn't necessarily grant full control over the server or allow for arbitrary code execution in the traditional sense. This leads to a nuanced discussion about the definition of RCE and the different levels of severity associated with various types of exploits.
Several users also share anecdotal experiences about encountering similar vulnerabilities in other games, highlighting the prevalence of such issues. They discuss the challenges of getting game developers to take security concerns seriously and the often slow response times in patching vulnerabilities.
Finally, some comments express appreciation for the author's detailed write-up and the clear explanation of the exploit, even with the omission of sensitive details. They commend the author for responsible disclosure and for bringing attention to an important security issue in the gaming industry. Overall, the comments provide valuable insights into the technical aspects of the exploit, the ethical considerations of vulnerability disclosure, and the broader implications for game security.