Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8ad502133ff9691…

MALICIOUS

PDF

81.0 KB Created: 2021-09-12 22:10:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: ae5bfa531ebdabe32d1038633b60062c SHA-1: 3d59ed2fd5923171bfc90ad063905fe9beab9511 SHA-256: a8ad502133ff96916388d27dd4e0ae22d583855f15039f695510830c74511147
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to various domains, suggesting a link farm designed to distribute content or manipulate search engine results. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, indicating a tactic to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jinanxintiandi.com/userfiles/files/24311255341.pdf In PDF document text
    • https://hetodon.com/fckeditorfiles/file/99717040836.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc71fc407c---70188042429.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/70120732267.pdfIn PDF document text
    • https://zenmobile.in/jaipriyart/uploads/files/92770310956.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/39631354710.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-7/20210907074340679853.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/tovepigidigigeb.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/49617773202.pdfIn PDF document text
    • http://eyupsifalibitkiler.com/resimler/files/xutumo.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/kilabawutuworasediduk.pdfIn PDF document text
    • http://aydinservis.com/ckfinder/userfiles/files/waxevugid.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/26988994697.pdfIn PDF document text
    • http://kkc1.org/htdocs/cljr/data/files/tudovilelorawopumomu.pdfIn PDF document text
    • http://skyrybupaslaugos.lt/uploads/files/biged.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/81009082589.pdfIn PDF document text
    • http://dietaltop.com/userfiles/files/nuwawuvusowafe.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/mivuxezivirisid.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/bazej.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/65267241126.pdfIn PDF document text
    • https://radiosmile.hu/upload/file/wuritipimatapun.pdfIn PDF document text
    • http://cy2hand.com/userfiles/9689621673.pdfIn PDF document text
    • http://rayocazar.com/images/elfinder-1.1/files/file/85792641211.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/92509362676.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/22374118452.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=pdf+editor+free+apkPDF 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_off0000d9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D4 10264 bytes
SHA-256: c8232853526b48a09df6ea8aa1dfb16da8a931484f307c6b4efc96092a94826a
font_01_sfnt_off0000f10b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF10B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001091d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1091D 17752 bytes
SHA-256: 5aa7702e6eb8a51b2afd5fa429ace8a6860d4890b0b0fa726289a730ba1c03e1