Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a6961fbcbe75dc3…

MALICIOUS

PDF

78.1 KB Created: 2021-09-10 17:45:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f4c9bdb0e93bafde9f79a80856c46a50 SHA-1: 96b568451ea78af0196ca6f143e1a3d373abfe6d SHA-256: 4a6961fbcbe75dc34c72e292cac7fcbacb049c623498070ce4b4969c9960b43f
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier as malicious. It contains numerous embedded URLs pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to direct users to malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9904

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://by-express.com/upfiles/editor/files/kutekimafipemukuju.pdf In PDF document text
    • http://01host.ru/userfiles/files/ranebojugajapesizuseg.pdfIn PDF document text
    • http://askaudit.ru/price/kizisozosatikek.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/wunabar.pdfIn PDF document text
    • https://aarhuskortet.dk/images/file/20017529045.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/26957399260.pdfIn PDF document text
    • http://gamebonda.com/ckupload/files/53658182561.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/96706224735.pdfIn PDF document text
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/98638600845.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/rovegubimilugogezumeloram.pdfIn PDF document text
    • http://puebloexec.com/userfiles/file/xekufakawavewa.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/feputol.pdfIn PDF document text
    • https://permargi.com/files/galeria/files/51584070982.pdfIn PDF document text
    • https://cosmopolitanhotel.lastrada.bg/uploads/wysiwyg/files/82831950875.pdfIn PDF document text
    • https://brukspec.pl/upload/file/rudupuwolibojo.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305f59cd820---43050836237.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16132a7fbc0981---96439105199.pdfIn PDF document text
    • https://nordavril.com/userfiles/file/fezotubasobojivajikaxaw.pdfIn PDF document text
    • https://grootformaatspandoeken.nl/userfiles/file/xegun.pdfIn PDF document text
    • https://anbc31.iscriptscloud.com/app/webroot/files/file/83082751964.pdfIn PDF document text
    • https://satuldelut.ro/ckfinder/userfiles/files/79089450056.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16131121c4bf26---javepamor.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/d9ec2c9897a154016bd3f95ea8e25d05/74791109193.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/70721936873.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/xadudirojovez.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=my+little+pony+apk+downloadPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d34e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD34E 10400 bytes
SHA-256: 78eb6f64e2d1e4fcad2918e607179535a12af27bab551e274d166d5f505b7c7f
font_01_sfnt_off0000eaf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAF9 17988 bytes
SHA-256: 94e0639d920896538522892132c6b379df14fb5c01f6e2cd1bfadcbdca9852a5
font_02_sfnt_off0001198a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1198A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1