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NCSC-TAD-2106-003
Reference No.: NCSC-TAD-2106-003CVSS 0
PuzzleMaker Threat Group Attacks Windows Devices
- Threat Type:
- N/A
- TLP:
- CLEAR
- CVE:
- CVE-2021-21220, CVE-2021-21224, CVE-2021-31955, CVE-2021-31956
Overview
The recently patched vulnerabilities in Microsoft Windows and Google Chrome have been used in highly targeted attacks against the enterprise by a threat group called PuzzleMaker. The advisory describes the use of Google Chrome vulnerabilities CVE-2021-21220 and CVE-2021-21224 for initial access, followed by Windows vulnerabilities CVE-2021-31955 and CVE-2021-31956. The attack chain deploys a malware dropper that installs a remote shell capable of uploading files, creating processes, and self-destruction.
Affected Technologies
- Google Chrome V8 JavaScript engine
- Microsoft Windows
- Windows NTFS
Mitigation and Immediate Actions
- 01
Immediately patch the vulnerabilities (CVE-2021-21220 and CVE-2021-21224) by upgrading Google Chrome to the latest version.
- 02
Immediately patch the vulnerabilities (CVE-2021-31955 and CVE-2021-31956) by upgrading Microsoft Windows to the latest version.
References
- PuzzleMaker attacks exploit Windows zero-day, Chrome vulnerabilities. (n.d.). Retrieved from ZDNet(opens in a new tab)
- PuzzleMaker attacks with Chrome zero-day exploit chain. (n.d.). Retrieved from Securelist(opens in a new tab)
- Windows 10 targeted by PuzzleMaker hackers using Chrome zero-days. (n.d.). Retrieved from BleepingComputer(opens in a new tab)

