Malicious PDF — malware analysis report

Static analysis result for SHA-256 425a03ac89e32c0b…

MALICIOUS

PDF

73.2 KB Created: 2021-09-01 02:21:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e4a0bc2ab6f04e5050ae7eb300d147cc SHA-1: 475c9858a68e6ed534404da37f3d81bc409a9f7f SHA-256: 425a03ac89e32c0b8e0450d192d3d158b8e3c84dea96788717cffc78a4a19fbd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to websites hosted on compromised WordPress installations, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the links and the heuristic firings point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://crewmak.ru/uplcv?utm_term=how+many+16.9+bottles+of+water+is+64+oz PDF link annotation
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0b39ed91e---reketiwasuxuzarerujafofiv.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/gamitep.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/8816444978.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/xatexerotegiduwi.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089adc24727b---32559539014.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/47799664655.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/1iocn9h2v2jqq6l0tf9fa95qjn/lubiwosojevivejowipibojuf.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cafac3facb---99210393595.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/sugovupufirenixikopubebuw.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/besufupof.pdfIn PDF document text
    • http://studioaeditecne.it/userfiles/file/96916281924.pdfIn PDF document text
    • https://coebmsf.com/userfiles/file/5195018753.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/lilor.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/sigeninaxiwuboluguluxa.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd00f57f09d---widavozokomatone.pdfIn PDF document text
    • http://jjinline.org/file_upload/file/jidad.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2958a8387---28696217765.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a06ac88fde5---binovebopozoziwuz.pdfIn PDF document text
    • https://purefeeling8.com/data/file/93226347368.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/kiwapowerunikozi.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/8188584921.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_off0000bc7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC7D 11296 bytes
SHA-256: 191ff83cdfb56989ab6f28434eeaa77c877e071df83babeaa479f35f99160bc6
font_01_sfnt_off0000d728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD728 16000 bytes
SHA-256: 62d8bff817686ca3bb3e9576afcd41a1ba2ea5231cec70c9da9b250ee65489db
font_02_sfnt_off0000ffbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1