Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7feec59d694bd6c…

MALICIOUS

PDF

73.0 KB Created: 2021-09-20 01:50:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b21b6f32753115d2e916ba6ac57424ee SHA-1: cf909d40533882193d700e51ed860518ef5487ec SHA-256: b7feec59d694bd6c264b4ab262bf790f71b636fab4ea9a3921efb292b27d2325
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised websites hosted on disposable domains. The embedded URLs, such as http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147b8fa73163---bitosuteviju.pdf, are likely part of a phishing or SEO poisoning campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147b8fa73163---bitosuteviju.pdf In PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd70ce7c3a---ritalajopubunixupuxi.pdfIn PDF document text
    • http://gesundheit-im-blog.de/userfiles/file/tixivigomeroweda.pdfIn PDF document text
    • http://ntvietnga.com/upload/files/mijaletom.pdfIn PDF document text
    • http://kamakuralosgatos.com/uploads/files/zigakirojajoveg.pdfIn PDF document text
    • https://prospr.fr/ckfinder/userfiles/files/47894679916.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/0ol8rahp2nmr3vhdq3cbgjio7m/sajovukezibesafewo.pdfIn PDF document text
    • https://seger.cz/userfiles/file/76541971166.pdfIn PDF document text
    • http://stavclearing.ru/upload/files/43771046578.pdfIn PDF document text
    • http://flixgolf.com/ckeditor/ckfinder/userfiles/files/kisopoparigapuluxurasu.pdfIn PDF document text
    • https://familienbilstrup.dk/ckfinder/userfiles/files/80877397538.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/88158373638.pdfIn PDF document text
    • http://toptoptraining.ru/img/upload/file/81866222985.pdfIn PDF document text
    • https://gemma.lucien-sv.info/uploads/files/614353e4b68fd.pdfIn PDF document text
    • http://kprmk.pl/userfiles/file/45859141175.pdfIn PDF document text
    • https://nstyapi.com/resimler/files/96219167154.pdfIn PDF document text
    • http://obraz-tlt.ru/userfiles/file/41195521256.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1630978230.pdfIn PDF document text
    • https://alcoquimicos.com/ckfinder/userfiles/files/sopilupupogudulabuxan.pdfIn PDF document text
    • http://www.asap-recruitment.net/upload/file/lamifabiligiweku.pdfIn PDF document text
    • https://wotfiles.com/ckfinder/userfiles/files/71422527383.pdfIn PDF document text
    • http://shriramashramps.org/userfiles/file/geloreroxafezafa.pdfIn PDF document text
    • http://77owship.netsociality.com/upload/files/83738576500.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143cf8d4905e---vosebununisepojorinameg.pdfIn PDF document text
    • http://tnslib.net/userfiles/files/78719676113.pdfIn PDF document text
    • http://preiss.at/upload_files/files/4044968209.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/28090223760.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=uninstall+work+profile+androidPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • 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_off0000bc22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD439 10676 bytes
SHA-256: d7d886a5e418a392538e85ac1b946c5084ec10ca24f9bdcc53c7230760a66317
font_02_sfnt_off0000ece0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE0 15932 bytes
SHA-256: 9bb35af91ad45d496f14f20833af35a255b4585b7963150060ef782e554be772