Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5f54ae3f427c9c8…

MALICIOUS

PDF

83.4 KB Created: 2021-09-20 08:23:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8b2bace83bef1f2faadc58ff1ad11c6a SHA-1: bcc0e57b331b9782fca03a0b8a7faf46d4045e80 SHA-256: e5f54ae3f427c9c8cd25a2e27cb15363f54a463b172b42bd970a55ae688433cb
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories. The ML classifier strongly indicated maliciousness, and the PDF link farm heuristic suggests a non-legitimate use of these links. The primary purpose appears to be directing users to external sites, potentially for further exploitation or malicious content delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://laborke.ru/uplcv?utm_term=mobile+imei+changer PDF link annotation
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614575859aede---kojudafoxam.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/1003068350.pdfIn PDF document text
    • http://klm-co.ru/foto/ck/files/92209602654.pdfIn PDF document text
    • https://praktijk.zorglink.nl/ckfinder/userfiles/files/91871425774.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/miduger.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c98687fc8---43159339702.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/84496409576.pdfIn PDF document text
    • http://3gr-group.com/ci/userfiles/files/16900971867.pdfIn PDF document text
    • https://highrise.pl/file/4099498803.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/nonexaxedesomatojiwor.pdfIn PDF document text
    • https://eltechma.com/zdjecia/fck/file/21621402944.pdfIn PDF document text
    • https://sim2007.com/files/57223098509.pdfIn PDF document text
    • http://tydafa.com/dafa/uploadfiles/20210911145050.pdfIn PDF document text
    • https://dichvumayphoto.vn/webroot/img/files/gulobezojesodajufeligoxa.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/23086541333.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/pa92ighjpgm0t77ig0h999aes1/julodulenokuduzunufezi.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613274981498d---10848524412.pdfIn PDF document text
    • https://radio-clipa.ro/userfiles/file/85667079962.pdfIn PDF document text
    • https://webmenuplus.com/images/file/luxikaxokot.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16137ff9b981ae---pufexisiwelareromuzesabi.pdfIn PDF document text
    • https://kalimati.in/userfiles/file/paxufazudoxolamumewawuz.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/karaweneretovulojod.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/8rg36aqnj7k6movupuqn0clkd9/82005695292.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_off0000e244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE244 17804 bytes
SHA-256: 0fcd6c55b734786f768f7793300efcc6b3f145776240fb5af15c0e54182e10f6
font_01_sfnt_off000110ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110AB 10544 bytes
SHA-256: cacfacec171ed74cae89f01a03a1bcf7853b20de186e5723e6aa3e92c8544162
font_02_sfnt_off0001286b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1286B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1