rule Careto { meta: author = "AlienVault (Alberto Ortega)" description = "TheMask / Careto generic malware signature" reference = "www.securelist.com/en/downloads/vlpdfs/unveilingthemask_v1.0.pdf" strings: /* General */ $name1 = "Careto" ascii wide $s_1 = "GetSystemReport" ascii wide $s_2 = "SystemReport.txt" ascii wide $s_3 = /URL_AUX\w*=/ ascii wide $s_4 = /CaretoPruebas.+release/ /* Certificate */ $sign_0 = "Sofia" $sign_1 = "TecSystem Ltd" $sign_2 = "<<>>" wide /* Encryption keys */ $rc4_1 = "!$7be&.Kaw-12[}" ascii wide $rc4_2 = "Caguen1aMar" ascii wide /* http://laboratorio.blogs.hispasec.com/2014/02/analisis-del-algoritmo-de-descifrado.html */ $rc4_3 = {8d 85 86 8a 8f 80 88 83 8d 82 88 85 86 8f 8f 87 8d 82 83 82 8c 8e 83 8d 89 82 86 87 82 83 83 81} /* Decryption routine fragment */ $dec_1 = {8b 4d 08 0f be 04 59 0f be 4c 59 01 2b c7 c1 e0 04 2b cf 0b c1 50 8d 85 f0 fe ff ff} $dec_2 = {8b 4d f8 8b 16 88 04 11 8b 06 41 89 4d f8 c6 04 01 00 43 3b 5d fc} condition: $name1 and (any of ($s_*)) or all of ($sign_*) or any of ($rc4_*) or all of ($dec_*) } rule Careto_SGH { meta: author = "AlienVault (Alberto Ortega)" description = "TheMask / Careto SGH component signature" reference = "www.securelist.com/en/downloads/vlpdfs/unveilingthemask_v1.0.pdf" strings: $m1 = "PGPsdkDriver" ascii wide fullword $m2 = "jpeg1x32" ascii wide fullword $m3 = "SkypeIE6Plugin" ascii wide fullword $m4 = "CDllUninstall" ascii wide fullword condition: 2 of them } rule Careto_OSX_SBD { meta: author = "AlienVault (Alberto Ortega)" description = "TheMask / Careto OSX component signature" reference = "www.securelist.com/en/downloads/vlpdfs/unveilingthemask_v1.0.pdf" strings: /* XORed "/dev/null strdup() setuid(geteuid())" */ $1 = {FF 16 64 0A 7E 1A 63 4D 21 4D 3E 1E 60 0F 7C 1A 65 0F 74 0B 3E 1C 7F 12} condition: all of them } rule Careto_CnC { meta: author = "AlienVault (Alberto Ortega)" description = "TheMask / Careto CnC communication signature" reference = "www.securelist.com/en/downloads/vlpdfs/unveilingthemask_v1.0.pdf" strings: $1 = "cgi-bin/commcgi.cgi" ascii wide $2 = "Group" ascii wide $3 = "Install" ascii wide $4 = "Bn" ascii wide condition: all of them } rule Careto_CnC_domains { meta: author = "AlienVault (Alberto Ortega)" description = "TheMask / Careto known command and control domains" reference = "www.securelist.com/en/downloads/vlpdfs/unveilingthemask_v1.0.pdf" strings: $1 = "linkconf.net" ascii wide nocase $2 = "redirserver.net" ascii wide nocase $3 = "swupdt.com" ascii wide nocase condition: any of them }