Malicious PDF — malware analysis report

Static analysis result for SHA-256 a90d7af5fbcd2950…

MALICIOUS

PDF

74.8 KB Created: 2021-07-22 09:27:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ab1e0f726e673a923a04a9514681b375 SHA-1: aab6f72544f90f98bacfb40d71c1fb47c1cbc44f SHA-256: a90d7af5fbcd2950a84ee49ffb85010af57a39cb5ec4eb382d2ce24cb50633f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting an attempt to lure users to malicious content. ClamAV detection and ML classification strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and link farm behavior are indicative of phishing or malware distribution attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb8495b061---moneneforokiresatezulofa.pdf
    • http://naszymsladem.pl/upload/file/wigiz.pdf
    • http://jfk1969nola.com/clients/873000/File/dinon.pdf
    • http://ksklinika.ru/ckfinder/userfiles/files/xenogara.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606e8650741f8---74467111145.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/321bfac7d530894300283729e1a6c003/xogojoda.pdf
    • http://cuatudongsaigon.vn/uploads/files/87251382738.pdf
    • http://absolutelyneon.com/userfiles/file/fasijogejugisotizotexev.pdf
    • http://macautemple.com/userfiles/file/38116121323.pdf
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160939ec0ea5dd---bivij.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/c48b7e304ec807e6b9489548563b5854/maxewibitine.pdf
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/160748a4ae6946---19261273921.pdf
    • https://aawyx.com/sites/default/imageuser/file/soxinigipezaxev.pdf
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1606ee2eb0fea6---87179782051.pdf
    • https://biomedchita.ru/imeg_master/file/23156126629.pdf
    • https://soechi.com/userfiles/file/gilijiwikumojagofidodizum.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1608d124ee0f34---mepedoxadikudijadegoze.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7adf75948---45197165503.pdf
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e2cacc44c31---68613691991.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/5a9c42691e4efadc6915efaf561ad77d/bomajuga.pdf
    • https://betentour.com/sites/default/files/file/vapejamujusoxokotolenuze.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=primary+empirical+research+articles
    • 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_off0000c423.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC423 16792 bytes
font_01_sfnt_off0000dc3a.bin
3a1155da9083de47f4cbc517aa00ebbfaf0a297702ceddb43d51a1399f99295c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC3A 10528 bytes
font_02_sfnt_off0000f434.bin
2e633cbe5c968e1462b4cb8637289a0f5cd61818dc649c5562e1acfb000a3bca
pdf-font-stream PDF embedded font (sfnt) at offset 0xF434 16336 bytes