Malicious PDF — malware analysis report

Static analysis result for SHA-256 350d1288bb5d91e8…

MALICIOUS

PDF

80.4 KB Created: 2021-09-18 11:27:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d2db8b960a1fa3d9f02078d4b6cc78d7 SHA-1: 8b8d57c82173230dd7db6371179686fc6a5e2ed5 SHA-256: 350d1288bb5d91e8fb46e30047af673dbc3bde3f8da0e10b5728f2c273305b7f
156 Risk Score

Malware Insights

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

The file is a PDF document identified as malicious by ML classifiers and ClamAV. It functions as a link farm, hosting numerous URLs that point to compromised WordPress upload directories. These links are likely designed to redirect users to malicious or phishing content, exploiting the trust associated with document attachments. No scripts were extracted, and the document body was unreadable, but the heuristic firings strongly indicate a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613944cd2d78f---mizawejilenopar.pdf In PDF document text
    • http://www.ecvbrass.ch/user/web/file/81694913070.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369ba67326d---jipalilosevapom.pdfIn PDF document text
    • http://th-hl.com///upload/files/mobasew.pdfIn PDF document text
    • https://cfacgroup.com/uploads/FCK_files/file/68059755641.pdfIn PDF document text
    • http://naturabliskociebie.pl/userfiles/file/81434709983.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/8a85f7078706c6ca84b438efd3eb9d26/83535766311.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343ede8efac---63139205980.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/48628892450.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/lajevuredasowen.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/72620305572.pdfIn PDF document text
    • http://fotocaroli.it/userfiles/files/5929842852.pdfIn PDF document text
    • http://garmaclima.com/uploads/ckfinder/files/sopilawaper.pdfIn PDF document text
    • http://autoachtercamper.nl/userfiles/file/jijediva.pdfIn PDF document text
    • https://trongtrucsolution.com/uploads/files/tirululujevevedaduvativ.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/53759881418.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613c63ba2315d---28011341232.pdfIn PDF document text
    • https://denimder.org/resimler/files/23997986884.pdfIn PDF document text
    • https://aquaprosmart.com/userfiles/files/16157337165.pdfIn PDF document text
    • http://montesantangelo.it/files/files/jezazepatusorutawumupato.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/13882739974.pdfIn PDF document text
    • http://phrabat.net/UserFiles/File/48229221460.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=android+windows+isoPDF 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_off0000d6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF08 18340 bytes
SHA-256: 906f7defefb4882a5473ee6fa6dece48e68e5c83ed33c4f93bfed8d5e2fd622b
font_02_sfnt_off00011ed0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED0 9872 bytes
SHA-256: 631f8f0fede410c8bc413bd62517bdb00a66672128f1742f79c0b5a0d9b3abc2