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Vol. 1 · Ed. 2026
CyberGlossary
Entry № 026

Agent Tesla

Agent Tesla とは何ですか?

Agent TeslaA .NET-based remote access trojan and information stealer active since 2014, sold openly as a commercial product and distributed primarily through phishing emails carrying malicious Office documents and archive attachments.


Agent Tesla is a .NET-based info-stealer and remote-access trojan that has been continuously active since 2014, sold openly as a 'monitoring' product on its own clearnet site and through reseller channels. It exists in dozens of slightly different versions because affiliates routinely repack the binary. Capabilities include keystroke logging, clipboard capture, screenshot capture, webcam access, theft of browser passwords and cookies, mail client credentials (Outlook, Thunderbird, FoxMail), VPN client credentials, FTP credentials, and exfiltration over SMTP, FTP, HTTP, or Telegram bots. The dominant infection vector is phishing email: lure documents embed Equation Editor (CVE-2017-11882, CVE-2018-0802) exploits or contain malicious archive attachments delivering a loader stage. Agent Tesla is one of the longest-running commodity stealers and routinely tops monthly malware ranking reports from anti-spam vendors, especially in business-email-compromise-adjacent campaigns. Defenses include disabling Office Equation Editor, attachment-detonation sandboxes, and EDR detections on the common loader behaviors (process hollowing into RegSvcs.exe, AspNetCompiler.exe).

  1. 01

    A phishing email with subject 'PURCHASE ORDER' delivers a .iso containing an Agent Tesla loader that exfiltrates Outlook stored credentials via SMTP.

  2. 02

    An EDR rule alerts on RegSvcs.exe making outbound SMTP connections to a non-corporate mail server — a near-pathognomonic Agent Tesla pattern.

よくある質問

Agent Tesla とは何ですか?

A .NET-based remote access trojan and information stealer active since 2014, sold openly as a commercial product and distributed primarily through phishing emails carrying malicious Office documents and archive attachments. サイバーセキュリティの マルウェア カテゴリに属します。

Agent Tesla とはどういう意味ですか?

A .NET-based remote access trojan and information stealer active since 2014, sold openly as a commercial product and distributed primarily through phishing emails carrying malicious Office documents and archive attachments.

Agent Tesla はどのように機能しますか?

Agent Tesla is a .NET-based info-stealer and remote-access trojan that has been continuously active since 2014, sold openly as a 'monitoring' product on its own clearnet site and through reseller channels. It exists in dozens of slightly different versions because affiliates routinely repack the binary. Capabilities include keystroke logging, clipboard capture, screenshot capture, webcam access, theft of browser passwords and cookies, mail client credentials (Outlook, Thunderbird, FoxMail), VPN client credentials, FTP credentials, and exfiltration over SMTP, FTP, HTTP, or Telegram bots. The dominant infection vector is phishing email: lure documents embed Equation Editor (CVE-2017-11882, CVE-2018-0802) exploits or contain malicious archive attachments delivering a loader stage. Agent Tesla is one of the longest-running commodity stealers and routinely tops monthly malware ranking reports from anti-spam vendors, especially in business-email-compromise-adjacent campaigns. Defenses include disabling Office Equation Editor, attachment-detonation sandboxes, and EDR detections on the common loader behaviors (process hollowing into RegSvcs.exe, AspNetCompiler.exe).

Agent Tesla からどのように防御しますか?

Agent Tesla に対する防御は通常、上記の定義で述べたとおり、技術的統制と運用上の実践を組み合わせます。

Agent Tesla の別名は何ですか?

一般的な別名: AgentTesla, OriginLogger (rebrand)。

関連用語