Malicious PDF — malware analysis report

Static analysis result for SHA-256 61ab53634a85eaaf…

MALICIOUS

PDF

67.8 KB Created: 2021-08-22 01:06:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f6beb723d871637e6e216412da8db385 SHA-1: 49496e034f58d18a009091989f264bb860cac777 SHA-256: 61ab53634a85eaaf539c8f7377b790b266e28e97a6e3e1262739ac7f60cc47f7
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF contains embedded JavaScript, which is a common technique for executing malicious code. The sample also features a link farm pointing to multiple distinct hosts, several of which are hosted on compromised CMS upload storage, suggesting an attempt to distribute further payloads or conduct phishing. ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5668

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://intersensor.ro/v2011/Files/fck_upload/file/25357230061.pdf In PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/3646682508.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160761a3d1b328---73942117707.pdfIn PDF document text
    • http://jarosi.hu/files/file/36688108272.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/8671f671180f8a4db71a11923fd89a65/wonunudinamofadivadibad.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/ih8vou9epjtggjjodclikv6sha/62103951767.pdfIn PDF document text
    • http://agavietnam.com/img/files/8266046972.pdfIn PDF document text
    • http://traiteur-ribot.fr/userfiles/file/43351535760.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdef4051c8f---88974402329.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611d46f3ab61f---relodedo.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/34599319799.pdfIn PDF document text
    • https://rux-thai.com/ckfinder/userfiles/files/kifetenirujebanum.pdfIn PDF document text
    • https://noble-program.site/js/ckfinder/userfiles/files/95752527932.pdfIn PDF document text
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/mnnf8tv3u1cchi8iscgr1uov5l/63044453027.pdfIn PDF document text
    • https://grootformaatspandoeken.nl/userfiles/file/toginigosanaxidijunezu.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/c50acc05c3bcb3d2878ba04ca193e79c/gevolokav.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/92854962529.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/8cf2f54bc2fd2168a53c7ed2251a4c95/15423047304.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d97f2ec76---tolir.pdfIn PDF document text
    • https://drvishweshwari.in/userfiles/file/towapalamajaluwatijufalal.pdfIn PDF document text
    • http://hzdsbg.com/uploadfile/1621102787.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/81666b4776fc0f01c680f6dc6b02e059/5487386267.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+clean+carpet+with+bissell+proheat+2xPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF08 10908 bytes
SHA-256: f7cc6c35a6c3659cf97def1fdbd8811805ce17454615226daad1334149d77d0b
font_01_sfnt_off0000f809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF809 16400 bytes
SHA-256: b4c78cc6e5c2960eab4c85e13f7ceeee32fbf3afecd474ad803e35c5d6624684