Malicious PDF — malware analysis report

Static analysis result for SHA-256 28fa4a738a65f66b…

MALICIOUS

PDF

99.3 KB Created: 2021-07-14 02:53:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c230934e4770e31ab68dd82a97bcb1af SHA-1: bda52bda1945505da7ca46d3a994b5d5e99d5062 SHA-256: 28fa4a738a65f66b9b1f0ae5ce230cbc729048ea3aeafc5b2134acae5c54dc63
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised websites, suggesting a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this by indicating the PDF acts as a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://queure.ru/uplcv?utm_term=system+of+linear+equations+matrix
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/qtcbsbgbkudsa94tdtbs8umrek/37595474665.pdf
    • http://ascensionchina.com/userfiles/file/69076614841.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/bgih62125hktp3154agl3h0vf6/ruwep.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/45e18ff45ba03dabc95b98f1c443142a/22152392719.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16079e756450d9---jabikibexusiwe.pdf
    • http://2ds-creations.fr/userfiles/file/60348648617.pdf
    • http://digitalpolicycouncil.com/imagenes/file/lopafikifonozinivusogexap.pdf
    • http://galgalesh.com/userfiles/file/44760094298.pdf
    • https://chptravel.ir/data/file/54727974589.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/997bd1a753ccfa0459ea2eed1ff4eb3d/taxologorateguj.pdf
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/c8634679bec657496fe1a93fe65e18a4/88223681682.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/mcs40i65scgk4160on3cerarm2/metovurajudotixowana.pdf
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160ad538357d89---nibegutijin.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/3qku0qmk37qp0050gqnvsdpkr1/94165598082.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b84e0e9e66d---zarigo.pdf
    • http://altelaw.com/uploads/image/file/wipoxaxabotusos.pdf
    • http://ecovn.vn/uploads/news_file/66175297539.pdf
    • http://divorce-difficile.fr/userfiles/file/77428710845.pdf
    • http://iglozawiercie.pl/zdjecia/file/23828626168.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/559f52de2c0493cb3283dba10f34e10f/tojuxisafivutitum.pdf
    • http://cepsagibyachtfuels.com/images/photos/19070973483.pdf
    • http://yakutiaprime.ru/SITE/files/editor/file/11691941847.pdf
    • http://meble-tk.pl/userfiles/file/88740185116.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_off000121bd.bin
4f820e31a7c052bcaeda1356dd2ea8a613742741497f5f3e8ab9f7e02c79054e
pdf-font-stream PDF embedded font (sfnt) at offset 0x121BD 10912 bytes
font_01_sfnt_off00013aff.bin
3cccca9427e6482658bdf72bff60a7d681956cfe030ac10493725e45a7d1ba8d
pdf-font-stream PDF embedded font (sfnt) at offset 0x13AFF 17144 bytes
font_02_sfnt_off0001680c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1680C 16792 bytes