Malicious PDF — malware analysis report

Static analysis result for SHA-256 021f281833d54f99…

MALICIOUS

PDF

71.6 KB Created: 2021-09-19 15:04:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9d86e2c30b65ff765a2633cbf78b7b70 SHA-1: bda28ad6d8dc59ce6961866932d2314056c34e3c SHA-256: 021f281833d54f99b24586cb86f1dfe32babea572724448524d83df6f4a1cb23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of external URI heuristics and link farm indicators further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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=amharic+keyboard+apk+download+for+pc
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/b54b49ede534def7a2161845db2af8eb/munegaraluzipupumaxadabe.pdf
    • https://adrfarysz.pl/userfiles/file/tagokob.pdf
    • https://artgreen.vn/attachment/files/82930877088.pdf
    • http://www.aunay-sous-auneau.fr/ckfinder/userfiles/files/vutupulizofur.pdf
    • http://wxdyzs.com/userfiles/files/91921014944.pdf
    • https://whatproperty.ng/ckfinder/userfiles/files/zixifezo.pdf
    • http://studiorumeo.it/userfiles/files/buzofuzubomezijefarudiw.pdf
    • http://k2plusinterior.com/userfiles/90430441363.pdf
    • http://baracenter.be/userfiles/file/17628510982.pdf
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/22150798650.pdf
    • http://architettodrabeni.it/userfiles/files/dulalevo.pdf
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613edcfd2eb6f---zevowemumanefurez.pdf
    • http://ornito-silesia.eu/userfiles/file/935648755.pdf
    • https://gonguyenkhoi.vn/upload/files/80485859760.pdf
    • https://cargoservice.pl/cargoservice/userfiles/file/fudorawumekezokumapokuge.pdf
    • http://hatowo.com/app/webroot/uploads/files/33316697516.pdf
    • https://titishop.co/upload/files/84008656780.pdf
    • https://fundreamz.com/ckfinder/userfiles/files/79029965872.pdf
    • https://basealimentare.it/webroot/files/fck_uploads/File/jiwotakomuwemamusakunib.pdf
    • http://yildizteknikelektrik.net/resimler/files/49233289787.pdf
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/0de7d17c80e64292a56cfaeed269ed33/40415246422.pdf
    • http://thangmayedex.com/webroot/img/files/49576475509.pdf
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b4ff.bin
07b8ba877e127b6cd918301ccb83ee145b4af1b7122396e05a3e5af74e09946e
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4FF 11032 bytes
font_01_sfnt_off0000ce42.bin
1091973b01336ce2c42c80ff57c89cef56f4c47b559ecc9d5909be8d3ea6db64
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE42 16540 bytes
font_02_sfnt_off0000f91f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF91F 16792 bytes