Malicious PDF — malware analysis report

Static analysis result for SHA-256 213b0a4850dd0d0f…

MALICIOUS

PDF

80.7 KB Created: 2021-06-14 04:16:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 028da41eeec98c1cfabb0a20e8295fd3 SHA-1: 744e163b32eb8909915410851f34fadc539b4f7c SHA-256: 213b0a4850dd0d0f559424469cfacccff26cf2132c9a85e46f4ca176c5b4f489
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the exploitation of PDF vulnerabilities or social engineering to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://infrive.ru/uplcv?utm_term=free+editable+school+newsletter+templates PDF link annotation
    • https://melz-feu.ru/upload/30133728646.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160832e0bd09ea---65910915017.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file/%5C/xifupe.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/bkj14onv4csld3i7rcv7nspcd0/tajuguguxewi.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/temolugivexuriv.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609fdf00e5af5---6326698583.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/59560163715.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/nch1ojj97vgnesujfjosd6vlpp/wigilesiberabut.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b87f85da2c0---69728777951.pdfIn PDF document text
    • http://walkofagesvt.org/clients/0/0e/0e42319052772b195a43ba3ede0f03e0/File/82838353125.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4bf7392184---32834823191.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/4e48c85b4d11ed56fcac90ff153bd54b/70263908181.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/30285544817.pdfIn PDF document text
    • https://makeswebsites.com/clients/c/c8/c8c605999f3d8352d7bb792cf3fdb25b/File/81911781112.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/19044957140.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e1cbd7d1c1---jutezukegonowebuse.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f0a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A8 5288 bytes
SHA-256: b9ea4191875a60a79b46b17d7bffd584b96de58a2955e52858e71dd97fd6cb95
font_01_sfnt_off0001026e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1026E 10712 bytes
SHA-256: 7aa2f31f716053710920d168fa0ca03f25bde9ff7e2be91cd30c5fb48851a95d
font_02_sfnt_off00012712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12712 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c