JetBrains TeamCity | Breaking Cybersecurity News | The Hacker News

The threat actors behind the BianLian ransomware have been observed exploiting security flaws in JetBrains TeamCity software to conduct their extortion-only attacks. According to a  new report  from GuidePoint Security, which responded to a recent intrusion, the incident "began with the exploitation of a TeamCity server which resulted in the deployment of a PowerShell implementation of BianLian's Go backdoor." BianLian  emerged  in June 2022, and has since pivoted exclusively to exfiltration-based extortion following the  release of a decryptor  in January 2023. The attack chain observed by the cybersecurity firm entails the exploitation of a vulnerable TeamCity instance using  CVE-2024-27198  or  CVE-2023-42793  to gain initial access to the environment, followed by creating new users in the build server and executing malicious commands for post-exploitation and lateral movement. It's currently not clear which of the two flaws wer...

A new pair of security vulnerabilities have been disclosed in JetBrains TeamCity On-Premises software that could be exploited by a threat actor to take control of affected systems. The flaws, tracked as CVE-2024-27198 (CVSS score: 9.8) and CVE-2024-27199 (CVSS score: 7.3), have been addressed in version 2023.11.4. They impact all TeamCity On-Premises versions through 2023.11.3. "The vulnerabilities may enable an unauthenticated attacker with HTTP(S) access to a TeamCity server to bypass authentication checks and gain administrative control of that TeamCity server," JetBrains  said  in an advisory released Monday. TeamCity Cloud instances have already been patched against the two flaws. Cybersecurity firm Rapid7, which discovered and reported the issues on February 20, 2024, said CVE-2024-27198 is a case of authentication bypass that allows for a complete compromise of a susceptible server by a remote unauthenticated attacker. "Compromising a TeamCity server allows an at...

Threat actors affiliated with the Russian Foreign Intelligence Service (SVR) have targeted unpatched JetBrains TeamCity servers in widespread attacks since September 2023. The activity has been tied to a nation-state group known as  APT29 , which is also tracked as BlueBravo, Cloaked Ursa, Cozy Bear, Midnight Blizzard (formerly Nobelium), and The Dukes. It's notable for the supply chain attack  targeting SolarWinds  and its customers in 2020. "The SVR has, however, been observed using the initial access gleaned by exploiting the TeamCity CVE to escalate its privileges, move laterally, deploy additional backdoors, and take other steps to ensure persistent and long-term access to the compromised network environments," cybersecurity agencies from Poland, the U.K., and the U.S.  said . The vulnerability in question is  CVE-2023-42793  (CVSS score: 9.8), a critical security flaw that could be weaponized by unauthenticated attackers to achieve remote code exe...