Malicious PDF — malware analysis report

Static analysis result for SHA-256 56ef21ad03a33a0b…

MALICIOUS

PDF

85.0 KB Created: 2021-09-10 20:09:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e8291b5f435aa083442ffc975be169f9 SHA-1: 11ffd9a08838beeb7a703e4f35b19bd20e6d9c57 SHA-256: 56ef21ad03a33a0b59003535a892ca5ab1122ae4080dbc04022be427567391d2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a tactic to obscure the true destination and leverage potentially compromised infrastructure. The primary attack pattern involves directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50110851283.pdf
    • http://studiotecnicofrisoli.com/userfiles/files/45835388042.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac9c92af24---pogizozifek.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ae062703b---kasefu.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131fdb037316---60879600022.pdf
    • https://produse-zilan.ro/files/fokiroxofupivofofirisu.pdf
    • http://stolizstekla.ru/userfiles/file/wonozakaropa.pdf
    • http://colorsoftexas.com/ckfinder/userfiles/uploads/84156491201.pdf
    • http://af.ssla.ru/images/fornews/files/senuvolala.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb4c8ee888---65856678976.pdf
    • http://ruben.pl/ckfinder/userfiles/files/kenomovokuxiwikero.pdf
    • https://hunde-katzen.at/soubory/4030573625.pdf
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/1379876853.pdf
    • http://geologicatoscana.eu/userfiles/files/fosevanavozutogaxamunej.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f883f94b70---84019709883.pdf
    • http://hoilhpnqbthanh.com/upload/file/78295847566.pdf
    • http://theponghop.com/upload/files/54086326111.pdf
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/manuxu.pdf
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/29335916373.pdf
    • https://baigiangtoanhoc.com/upload/files/vodiwijorevefitiseji.pdf
    • http://wakesup.org/userfiles/file/lazekajoditamuwatuzizinu.pdf
    • https://atlantidegattico.it/file/tebakat.pdf
    • http://koreabulk.net/userData/board/file/85709409212.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=face+recognition+app+in+android
    • 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_off0000e7d3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D3 16792 bytes
font_01_sfnt_off0000ffea.bin
39b06560c86c8c1b830fa30ca46e9b3eff8fb96f95aea3341029c8c174df7d2a
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEA 10452 bytes
font_02_sfnt_off0001177e.bin
5f064c1698919875abfab6c9178c63763bb6104a595b8242ee9351b19523807c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1177E 18056 bytes