Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fa87865deef7978…

MALICIOUS

PDF

87.0 KB Created: 2021-09-10 22:10:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 176b2352483ce152c16f8c418d2359ba SHA-1: c686c8085307fcb0e838d77e087e4730877d99a7 SHA-256: 7fa87865deef79783b8964f438341885ca4ca804dc25417b8ef0a331ec2adf11
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to other PDF files, many hosted on disposable domains or potentially compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • 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://universalestetic.com/userfiles/file/94574625641.pdf In PDF document text
    • http://sreema.org/FCKeditor/file/23829529819.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/46939060258.pdfIn PDF document text
    • http://mutitar.com/user_img/files/titixolamov.pdfIn PDF document text
    • http://uzmansporzeminkaplama.com/resimler/files/wenajib.pdfIn PDF document text
    • http://studiotecnicobergamaschi.it/userfiles/files/zemefonuji.pdfIn PDF document text
    • http://thingsantiquesla.com/userfiles/files/67577283788.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/majudugeragunidala.pdfIn PDF document text
    • http://trips-in.com/ckupload/files/mulexazenepevakuwok.pdfIn PDF document text
    • http://geomanteia.com/userfiles/files/rudagesosekokupepem.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/pilibefolerexipatikix.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/9355695006.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133625424147---ravapiwiwaguwosego.pdfIn PDF document text
    • http://didula.com/img/file/83955404319.pdfIn PDF document text
    • https://efsanepin.com/calisma2/files/uploads/gatabaxikokasatedanafe.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613a6693e8261---konodin.pdfIn PDF document text
    • https://eko-briketes.lv/userfiles/files/sabofoku.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/r0l6o43pbih1n6n0se8c28871b/90330660469.pdfIn PDF document text
    • http://teleinwestor.com/userfiles/file/18359523110.pdfIn PDF document text
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/44260370178.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/79927443502.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/90504516179.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7030ccdc0---rozopexoriwetifab.pdfIn PDF document text
    • http://xn--90afqerdlt1f.xn--p1ai/admin/ckfinder/userfiles/files/vuduto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=cool+math+games+fireboy+and+watergirl+5+elementsPDF link annotation
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/12568243507.pdfIn PDF document text
    • 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_off0000ef5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF5F 17156 bytes
SHA-256: f89d1cb5c889b79a322f1ec15f424aef55a9fe95ec7fd907a8303b01912cee5e
font_01_sfnt_off00011b78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B78 11304 bytes
SHA-256: d5f93fe3194742baad968c570cd5e457f1d31824d95b3359108a60723c3012b4
font_02_sfnt_off000135cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1