Malicious PDF — malware analysis report

Static analysis result for SHA-256 081c7eb68f35c105…

MALICIOUS

PDF

77.3 KB Created: 2021-09-19 09:49:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 93f0c00ae9ed0bdb5a987728a99e8ed2 SHA-1: 6967530d055119b7e2e61fe8df49b30516347418 SHA-256: 081c7eb68f35c105829d27909fbc40d79e7e9c779c5f74a87c62e3419db8b0ae
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The embedded URLs and the nature of the heuristics strongly suggest an intent to redirect users to malicious or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://tweddlefoto.com/files_contenidos/upload/files/37999488157.pdf
    • https://taechoclub.com/FileData/ckfinder/files/20210903_C9B6DAE330C49F18.pdf
    • http://www.grupoaccs.net/ckfinder/userfiles/files/86639742056.pdf
    • http://gaushalango.com/uploaded_files/userfiles/files/jezowaninimegifa.pdf
    • http://strandedtattoo.net/file/31250823373.pdf
    • https://tcremich.lu/files/files/66889456396.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303ab5a0e42---61022638791.pdf
    • http://investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/rugufiz.pdf
    • https://www.hkfew.org.hk/ckfinder/userfiles/files/jekud.pdf
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/webaxew.pdf
    • https://hotelmitrutarija.com/uploaded/files/pawaguvidusomazeboxaxu.pdf
    • https://www.emcp-pmce.ca/_includes/ckfinder/userfiles/files/4589907709.pdf
    • https://epagneuls-bretons.fr/caningest/images/file/guwovekidozi.pdf
    • http://schokozentrale.de/idata/86990238817.pdf
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/6484715707.pdf
    • http://deltools.com/userfiles/file/virepasekixotanalogowawo.pdf
    • http://fishingas.com/userfiles/file/wemopemajos.pdf
    • http://year-c.com/upload_fck/file/2021-9-6/20210906095250290219.pdf
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/0b7e52372168eccc6a811c21d7d6d354/30084163455.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/s3ptog1n8fsa4tduttkch5hocs/9288886191.pdf
    • http://seibyou-koujien.com/files/files/pezopilizesoworajito.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137da1700439---22384483068.pdf
    • https://www.ijestr.com/ckfinder/userfiles/files/8499465418.pdf
    • https://fundacjaartfreeart.pl/userfiles/file/nijefukiva.pdf
    • http://uni-farm.pl/ckfinder/userfiles/files/gikolezawefiketed.pdf
    • https://equator-maritime.com/userfiles/file/sotusosofeb.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=percentage+change+from+negative+to+positive
    • 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_off0000ca0b.bin
11c321ec138548317d990e0a50903c1f1392cc6848e0767a05dc2a2f9dc4c8ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA0B 10948 bytes
font_01_sfnt_off0000e351.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE351 16792 bytes
font_02_sfnt_off0000fb63.bin
159ea453cb8d6b5f5da718dd5b442b3683a66f0be59c9983b66295cbbc8a0989
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB63 16620 bytes