Malicious PDF — malware analysis report

Static analysis result for SHA-256 987f93cc72fb982d…

MALICIOUS

PDF

106.8 KB Created: 2021-07-23 00:06:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b86651560df0ddf0abab845bc7273fdd SHA-1: 426912a022f0016385ef9a5f60d5b8d35c65c4f9 SHA-256: 987f93cc72fb982de281941c2f471d745b09c43131d604137f3ca72bd4dca369
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute further malicious content or conduct phishing. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9896

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b0e40879b08---26290328026.pdf In PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608dddf84e3e7---beridekiwid.pdfIn PDF document text
    • http://thegroverestaurantnj.com/userfiles/files/neriniwelojupuged.pdfIn PDF document text
    • https://eminencesolutions.in/resources/userfiles/file/loburarex.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/87999348470.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/udtf0bt7hknt9va216v6hn4usp/46724050225.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afb6ec8a601---vikiwezekisowapujorirafi.pdfIn PDF document text
    • http://starlightskiothon.ca/clients/4/44/44db284a3a4a6a3f34f8f2fa71918f98/File/tafumuropumovimesigej.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/d55a493dfe254a0fdde34b0d1b0d7c7b/subozikiti.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/523a02471993526c0ee5d03c1cdebaed/26539236172.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/68057244369.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606fde38ef7b0---38801276247.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/avctomu84gm7fpqm7b2gepnba4/zokotesoju.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/40145394503.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/782518688.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072ef3f15e1c---magoroxomefixijureriro.pdfIn PDF document text
    • https://chornakorn-packing.com/ckfinder/userfiles/files/22717046353.pdfIn PDF document text
    • https://10glazsikeyrosa.ru/file/92171068121.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/1608e878cc136e---58028178721.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/516a7690728468a7988fafeaba547250/nilarepotasolubufago.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fdcb52752e---78568745747.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/40423bb37ecb2cf654ded72fb20ca7a5/gipilulanufoz.pdfIn PDF document text
    • http://sancheonglittletheaters.com/upload/userfiles/2021/07/files/210716103012.pdfIn PDF document text
    • https://archielectronics.com/userfiles/files/mekasiletirebi.pdfIn PDF document text
    • http://2sisaccount.com/userfiles/files/kavoroxovoxosup.pdfIn PDF document text
    • https://mysmartedu.com/uploadimages/files/16696865573.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=rods+and+conesPDF link annotation
    • 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_off00013ca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CA6 18204 bytes
SHA-256: a779c9e4376734106b443c1f44e867b990c24be32a1683bf71d131afacf0b8f0
font_01_sfnt_off00016caf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16CAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000184c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x184C6 10072 bytes
SHA-256: e74fe18eedf7d383c22decd8625913f3cae1d8ab330896f9186d9915be1f5bf7