Malicious PDF — malware analysis report

Static analysis result for SHA-256 f75871c930822efe…

MALICIOUS

PDF

69.4 KB Created: 2021-05-27 18:46:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 688960268fc4fb17484b72bdd4e66dff SHA-1: 8cb92c3605f1263c71a8b4d37a2e368d94b135ce SHA-256: f75871c930822efe48591cdbd8b1763b59fdc2771fc8d8eb0a63a27a8d962d6b
196 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a link farm for distributing malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware delivery campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://rsun.pro/admin/ckfinder/userfiles/files/bufewop.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/73ec4c8d1c6863d490e2e95768d9a0b4/93397265486.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/34a55700e293b79a777107abf7691389/12468164371.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160778a5614179---dovaxorukulufunaxik.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/9a01b1bd9f5db5eacec86837fdf63ff1/juxolokizirebow.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/fa9148744425e8c01106217a8b18f80e/buxixokasodilij.pdf
    • http://novichiha.ru/pic/file/76828342676.pdf
    • http://www.darvidproperty.com/news/file/rejojovifanogodepabi.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/cm0odo84p0rie6qkvcu2pqfsdt/pisupaweta.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1b0a6ee7a---61973339230.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/t71nqcr2fm8uq32oiiloojfl3p/xidagufovukesirozu.pdf
    • http://rydelko.pl/userfiles/file/48562349347.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd04ad777f---pejuvuwalowetofugitaso.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/3e28354503822c052b2e586b1f32654e/liwopebowuxowebonati.pdf
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607618922f1b8---11945696478.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160983e85eb4b7---vadekexuwokujoxut.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=lymphatic+system+and+immune+response+review+sheet
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3dc.bin
21feb231f8c8615228193310f75a1ec1bccb480bcf9af050e9595e6c113df778
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3DC 5476 bytes
font_01_sfnt_off0000e66d.bin
c06cedc2f05ef16e0e60154cf67222a2374cbfec0715288be95758116447257a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE66D 10164 bytes