Trend Micro has uncovered active exploitation of CVE-2023-36025, leading to the discovery of a new malware strain named Phemedrone Stealer. This open-source stealer specifically targets web browsers, cryptocurrency wallets, and messaging apps like Telegram, Discord, and Steam. It collects sensitive data, including passwords, cookies, and authentication tokens, and sends the stolen information to attackers via Telegram or a command-and-control server. Despite the patch for CVE-2023-36025, the Cybersecurity and Infrastructure Security Agency (CISA) added it to the Known Exploited Vulnerabilities (KEV) list due to ongoing evidence of exploitation, highlighting the importance of organizations updating their Microsoft Windows installations.
To initiate the Phemedrone Stealer infection, attackers use malicious Internet Shortcut files hosted on platforms like Discord or cloud services. The files are often disguised using URL shorteners to trick users into opening them. Once executed, the malicious .url file exploits CVE-2023-36025, connecting to an attacker-controlled server to download and execute a control panel item (.cpl) file. Additionally, the attackers employ a second-stage loader known as Donut, an open-source shellcode enabling the execution of various file types in memory.
Upon execution, Phemedrone Stealer decrypts its configuration using a predefined salt and encryption key, revealing items like a Telegram API token, chat ID, and Email_To mutex. The malware then targets a wide range of applications and services to extract specific types of sensitive information, including browsers, cryptocurrency wallets, Discord, FileZilla, Steam, and more. Despite the patch, the text underscores the evolving sophistication of malware threats and the rapid integration of new exploits for critical vulnerabilities by malicious actors. Organizations are urged to update Microsoft Windows installations to mitigate the risk of CVE-2023-36025 exploitation.
