MALWARE FAMILY

FlawedAmmyy

Internal ID: win.flawedammyy

aliases

Last seen:Mar 17, 2026

Intelligence Profile

FlawedAmmyy is a well-known Remote Access Tool (RAT) attributed to criminal gang TA505 and used to get the control of target machines. The name reminds the strong link with the leaked source code of Ammyy Admin from which it took the main structure.

Threat Analysis

FlawedAmmyy is a malware family tracked by threat intelligence researchers and catalogued in the Malpedia dataset. It represents a distinct malicious software lineage with identifiable code characteristics, behaviors, and victimology.

External References

→https://attack.mitre.org/software/S0381/

→https://blog.intel471.com/2020/05/21/a-brief-history-of-ta505/

→https://blog.trendmicro.com/trendlabs-security-intelligence/ta505-at-it-again-variety-is-the-spice-of-servhelper-and-flawedammyy/

→https://go.crowdstrike.com/rs/281-OBQ-266/images/Report2020CrowdStrikeGlobalThreatReport.pdf

→https://habr.com/ru/company/pt/blog/475328/

→https://intel471.com/blog/a-brief-history-of-ta505

→https://secrary.com/ReversingMalware/AMMY_RAT_Downloader/

→https://threatrecon.nshc.net/2019/08/29/sectorj04-groups-increased-activity-in-2019/

→https://ti.qianxin.com/uploads/2020/02/13/cb78386a082f465f259b37dae5df4884.pdf

→https://web.archive.org/web/20161223002016/https://www.symantec.com/connect/blogs/odinaff-new-trojan-used-high-level-financial-attacks

Quick Facts

TypeMalware Family

Aliases1

Also Known As

win.flawedammyy

Research Links

MITRE ATT&CK VirusTotal Google (news) Twitter/X search

Data sourced from Malpedia, Ransomware.live, RansomLook, and CTIWATCH OSINT collection. Actor attribution is based on available intelligence and may be incomplete.

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