Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7c9cdb52aaf544d…

MALICIOUS

PDF

88.9 KB Created: 2021-08-25 15:18:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 904c02aa21f38dc145b0b1a126040124 SHA-1: ed5e51d997e8bbc08a411e888062f88a2967c9e7 SHA-256: c7c9cdb52aaf544dd4eb655d74c42526df0a7b6d8ed042d937677169a6f5d296
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/23ef6ee73857c5760ff77cb1cccc850c/somazugi.pdf In PDF document text
    • http://thucancakoihikari.com/luutru/files/nalirizatedupipo.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/7646996830.pdfIn PDF document text
    • http://uteambio.com/upload/files/12623243921.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082852a6a5f5---17085113823.pdfIn PDF document text
    • http://www.w.radeton.cz/ckfinder/userfiles/files/rosofozenesuliniga.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/35394189574.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/lexin.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/83eeb3c69e190067a3f4be10771d8a1e/wogosusagututaniwepo.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/poberewupagap.pdfIn PDF document text
    • https://signika.pl/Upload/file/xisipilunadaridofomexupuj.pdfIn PDF document text
    • http://vodnik48.ru/content/file/vamubiluvob.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/zimipogizekokanigejef.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/25907465432.pdfIn PDF document text
    • https://club-sports.net/uploads/products/files/23562390161.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5f1809ef7---mawumo.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779a98ecf5c---mezifirad.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/77170306868.pdfIn PDF document text
    • http://sdds.be/userfiles/file/zetujoze.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb74841537---purikurugagurimipoko.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/libozobapudowaniberobab.pdfIn PDF document text
    • https://tavio.ru/files/file/45488421555.pdfIn PDF document text
    • https://dmitrovka-zn.ru/admin/ckfinder/userfiles/files/fidabun.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/5635727061.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=android+message+archivePDF 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_off0000f662.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF662 17724 bytes
SHA-256: 3bf7c530002a1f9be9c2130aa9a7674e20d3cf14146c6688fe905a243aa82efb
font_01_sfnt_off0001250c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1250C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013d23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D23 10720 bytes
SHA-256: 286e5af63ac3c030bc33fd74d1c1ae5f33e486b8884983710770375cec9e2afd