Merge pull request kevoreilly#2847 from kevoreilly/doomedraven-patch-3

kevoreilly · web-flow · commit 557ac1f56306 · 2026-01-14T15:57:52.000Z
Update AgentTesla rule metadata and strings
diff --git a/data/yara/CAPE/AgentTesla.yar b/data/yara/CAPE/AgentTesla.yar
@@ -68,46 +68,50 @@ rule AgentTeslaV2 {
 
 rule AgentTeslaV3 {
     meta:
-      author = "ditekshen"
-      description = "AgentTeslaV3 infostealer payload"
-      cape_type = "AgentTesla payload"
+        author = "ditekshen"
+        description = "AgentTeslaV3 infostealer payload"
+        cape_type = "AgentTesla payload"
     strings:
-        $s1 = "get_kbok" fullword ascii
-        $s2 = "get_CHoo" fullword ascii
-        $s3 = "set_passwordIsSet" fullword ascii
-        $s4 = "get_enableLog" fullword ascii
-        $s5 = "bot%telegramapi%" wide
-        $s6 = "KillTorProcess" fullword ascii
-        $s7 = "GetMozilla" ascii
-        $s8 = "torbrowser" wide
-        $s9 = "%chatid%" wide
-        $s10 = "logins" fullword wide
-        $s11 = "credential" fullword wide
-        $s12 = "AccountConfiguration+" wide
-        $s13 = "<a.+?href\\s*=\\s*([\"'])(?<href>.+?)\\1[^>]*>" fullword wide
-        $s14 = "set_Lenght" fullword ascii
-        $s15 = "get_Keys" fullword ascii
-        $s16 = "set_AllowAutoRedirect" fullword ascii
-        $s17 = "set_wtqQe" fullword ascii
-        $s18 = "set_UseShellExecute" fullword ascii
-        $s19 = "set_IsBodyHtml" fullword ascii
-        $s20 = "set_FElvMn" fullword ascii
-        $s21 = "set_RedirectStandardOutput" fullword ascii
-
-        $g1 = "get_Clipboard" fullword ascii
-        $g2 = "get_Keyboard" fullword ascii
-        $g3 = "get_Password" fullword ascii
-        $g4 = "get_CtrlKeyDown" fullword ascii
-        $g5 = "get_ShiftKeyDown" fullword ascii
-        $g6 = "get_AltKeyDown" fullword ascii
-
+        // --- High Fidelity Indicators (Malware Specific) ---
+        $s_specific1 = "get_kbok" fullword ascii
+        $s_specific2 = "get_CHoo" fullword ascii
+        $s_specific3 = "KillTorProcess" fullword ascii
+        $s_specific4 = "GetMozilla" ascii
+        $s_specific5 = "torbrowser" wide
+        $s_specific6 = "bot%telegramapi%" wide
+        $s_specific7 = "%chatid%" wide
+        
+        // Known AgentTesla Typo (High Confidence)
+        $s_typo      = "set_Lenght" fullword ascii
+
+        // --- Config / Stack Strings (Unique data structures) ---
         $m1 = "yyyy-MM-dd hh-mm-ssCookieapplication/zipSCSC_.jpegScreenshotimage/jpeg/log.tmpKLKL_.html<html></html>Logtext/html[]Time" ascii
         $m2 = "%image/jpg:Zone.Identifier\\tmpG.tmp%urlkey%-f \\Data\\Tor\\torrcp=%PostURL%127.0.0.1POST+%2B" ascii
         $m3 = ">{CTRL}</font>Windows RDPcredentialpolicyblobrdgchrome{{{0}}}CopyToComputeHashsha512CopySystemDrive\\WScript.ShellRegReadg401" ascii
         $m4 = "%startupfolder%\\%insfolder%\\%insname%/\\%insfolder%\\Software\\Microsoft\\Windows\\CurrentVersion\\Run%insregname%SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\StartupApproved\\RunTruehttp" ascii
         $m5 = "\\WindowsLoad%ftphost%/%ftpuser%%ftppassword%STORLengthWriteCloseGetBytesOpera" ascii
+
+        // --- Generic Functions (Require other indicators to match) ---
+        // These are legitimate on their own, but suspicious in context
+        $s_generic1 = "set_UseShellExecute" fullword ascii
+        $s_generic2 = "set_IsBodyHtml" fullword ascii
+        $s_generic3 = "set_AllowAutoRedirect" fullword ascii
+        $s_generic4 = "set_RedirectStandardOutput" fullword ascii
+
     condition:
-        (uint16(0) == 0x5a4d and (8 of ($s*) or (6 of ($s*) and 4 of ($g*)))) or (2 of ($m*))
+        (
+            // 1. Strongest: Match any of the unique config blobs
+            2 of ($m*)
+        ) or (
+            uint16(0) == 0x5a4d and
+            (
+                // 2. Strong: Match specific malware function names
+                5 of ($s_specific*) or
+                
+                // 3. Combined: The Typo + Generic email/process functions
+                ($s_typo and 4 of ($s_generic*))
+            )
+        )
 }
 
 rule AgentTeslaV4
