Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb90ac7ec0fcd858…

MALICIOUS

PDF

82.0 KB Created: 2021-05-23 02:59:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0d40ed024236387624fd26f21214759d SHA-1: eced7c833ed68d9a83f9ab9fba65736566b9439b SHA-256: cb90ac7ec0fcd85871e6ac9932466a66bcebe80424b4e4fde9e1d5c26aa9c6dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or trojan payload. The document contains a link farm pointing to multiple compromised WordPress sites and disposable hosting domains, likely serving as a lure to download further malicious content. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing campaigns that leverage embedded links to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://hydrem.ru/images/file/51155365146.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/fgkkb6ugsoh8v01var4juaasn0/46477048597.pdf
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/bbd2b81365a67cf5e09e808c0b6f1320/gofima.pdf
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/fc783647c8d7cfbb6492d4f63e3871e8/xadomufimoje.pdf
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/0636d0998504507b3c63249bc8956995/baxorofimeloti.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/6e6f631276612cf128ac5cc797c2a61d/dijitulimuvopor.pdf
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/c462826991be9ec7b3465ca97cfc83cd/81234199418.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/31a0ff87e9b9e5071b6eab25d6ee4e11/79165103912.pdf
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/fk5ct06g2osgt8s4mrhd924vok/doveropili.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160979ac9198b8---nadajozafuxifa.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb1a8c20f4---31264491210.pdf
    • http://dreamcatcherltd.com/userfiles/file/51759887518.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606eaa3beccd5---xewuwibiwonuwala.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/68mrncg3if9t1ior7o2tlu1535/68839253109.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607749d147243---20437688156.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607da0fe05532---20047679608.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098d921278a8---90548511352.pdf
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16075aa92033da---gululemesixe.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=guia+para+examen+diagnostico+de+secundaria+inea+veracruz
    • 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://scripts.sil.org/OFL
    • 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_off0000e778.bin
c6f1ce9c398793e8a6ce4263b6ed5ce4fe0c298f7889cedfdcf4f51e444a497d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE778 5568 bytes
font_01_sfnt_off0000fa72.bin
8a82ae017aaee31361bdadc3d29db642475f6f13fef095cfa877357d653525e0
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA72 12748 bytes
font_02_sfnt_off0001236c.bin
1b804abd1363e4a356c9bee8c2bdca7f6bd30ecb4716293195913ecc5e29d1cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x1236C 16132 bytes