Malicious PDF — malware analysis report

Static analysis result for SHA-256 78e9fc49161c1870…

MALICIOUS

PDF

69.4 KB Created: 2021-09-28 13:34:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2a2130b1a341c4d8330cb40df0f0339d SHA-1: 9c86e36a9202aba69021aa5045cd2caf3ef7a4f8 SHA-256: 78e9fc49161c18708f069753358bbe1aaf29c3fad99584de23f68031d4017d1e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised WordPress sites or other disposable hosting. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to lure users to external sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/e52dc4c64bf1ea43b9780c1dbcbe93e1/2675604227.pdf In PDF document text
    • https://dpt-mh.com/uploads/news/files/xikopejefidemup.pdfIn PDF document text
    • http://ballmillfactory.com/d/files/49736016099.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/fawafiwusixofuxuzotu.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/30978449731.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f43133b8b4---nojilivoxoredixutiro.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/989505030e51a29f7b95d06a8f5db97b/8052338259.pdfIn PDF document text
    • https://yoimart.com/upload/file/20210908194700.pdfIn PDF document text
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vavalugaduzafewuwokiweki.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109130348228995.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/lomisajojolik.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613687e2a5ffe---welonoba.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/lobod.pdfIn PDF document text
    • https://karpzbeldowa.pl/uploads/userfiles/files/japoder.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/161365e77cb68a---vubopejapazovokalasiwes.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/mowaxatopavedudopade.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613767050ddb5---476309144.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210917110340.pdfIn PDF document text
    • http://deltools.com/userfiles/file/52129368808.pdfIn PDF document text
    • http://vollaracis.com/UserFiles/file/69290898337.pdfIn PDF document text
    • https://gites-les-bardots.com/userfiles/file/wekawujegab.pdfIn PDF document text
    • http://pronobile.com/catalog/file/14568307276.pdfIn PDF document text
    • http://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/79222467949.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=decrease+video+size+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_off0000b2fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2FE 10348 bytes
SHA-256: 70a0677d128e6785a258a153beb70dd2376f003504926ca8ab8b3855590268ed
font_01_sfnt_off0000ca80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA80 14780 bytes
SHA-256: b56817bbb157fe0bc22355d0e279b537de502df26411d29e2a884276e520edf3
font_02_sfnt_off0000ef87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1