Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3ef081fedf3d4b7…

MALICIOUS

PDF

80.4 KB Created: 2021-09-07 20:17:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 51c28071c3d477b9e7b1d021fe5746b2 SHA-1: 09d666bdcda9d46c7164446cfb0a970eae7b043f SHA-256: e3ef081fedf3d4b7d025c6f7591aaa7290b9a228dfd6eab6b98ca47e4fed84ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, indicating the document is designed to drive traffic to potentially malicious or compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://archism.ru/uplcv?utm_term=definition+of+geography+pdf PDF link annotation
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/36a67d3003f3ff66eff48fe768cdfb37/76854389017.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1609afad069af5---kosit.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160827579d8ec2---25148309523.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/gejek.pdfIn PDF document text
    • https://senfina.top/uploads/files/83156095399.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/c7ccfc4bdf91d34071f6cc746409fb52/nixupuw.pdfIn PDF document text
    • http://tao-ssct.org/data/upload/file/fobol.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160bb550a9301d---28619635612.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/5gqjfdce4sinlct6fs24tushpf/24907879535.pdfIn PDF document text
    • http://www.eurosecurimed.com/ckfinder/userfiles/files/kexokiduzusomuker.pdfIn PDF document text
    • https://itacademyindia.com/ckfinder/userfiles/files/84620436979.pdfIn PDF document text
    • http://sterkrade.net/ckfinder/userfiles/files/tubito.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/gefuwexopek.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/84012743922.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/bejes.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a6864c243d4---gupalon.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/57857806109.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/tifeguwaboduvawalur.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c54b18d44bc---65538603719.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091cb0a7b86f---28757382683.pdfIn PDF document text
    • http://stewartreunion2020.com/clients/2/2a/2a0d9dcdd57715375c9f4393c24df0f2/File/22338826517.pdfIn PDF document text
    • https://penzionradvanice.cz/res/file/57937343793.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160800591b3b8b---gawusosukesebaresoberiri.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a73870ca742---gemavusur.pdfIn PDF document text
    • http://tiga.co.th/ckfinder/userfiles/files/32192775355.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_off0000d712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD712 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF29 10680 bytes
SHA-256: 0f237d15c3549eec36fe49baa45cf6618329223bcc1b890aadcc66a78df2cfc7
font_02_sfnt_off0001075f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1075F 17276 bytes
SHA-256: f87937efe4df9185f8c4d73025d1fff55684a377ff30fcbca6231dbbf05c2c3e