Malicious PDF — malware analysis report

Static analysis result for SHA-256 ced858a0442bd8f7…

MALICIOUS

PDF

81.6 KB Created: 2021-06-26 23:33:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8b6733aaa821814b9f2cb1c071e32537 SHA-1: 941235cb25e4b4a6b3cb58f246cb7531c49e9c3e SHA-256: ced858a0442bd8f7b802a7797c6dfd67fc18723c010d81c41acf000041744d24
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of multiple external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4e9252520---tixivijitamu.pdf In PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160982afc187ff---90682255967.pdfIn PDF document text
    • http://netpost.vn/upload/userfiles/files/95842757825.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/14163003676.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1606d47099402e---rebipumugizelogolajomo.pdfIn PDF document text
    • http://schroniskoorzechowce.pl/ckfinder/userfiles/files/14266668641.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/bvknoe5o95rrl96er4sbplj015/26865506996.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc3438ad7c---nosadomutep.pdfIn PDF document text
    • http://nutricion-intravenosa.com/wp-content/plugins/super-forms/uploads/php/files/4120de131498f509683325ddc0f7904c/53187602688.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16080c84165261---87941341529.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/89144136806.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16074d9be3a79b---wosibodapobavakewo.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/ziwekunavopivimur.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607abcdaf1b97---rexatujewojakekiwib.pdfIn PDF document text
    • https://bamor.org/userfiles/file/fexuzo.pdfIn PDF document text
    • http://lightningriskassessment.com/ci/userfiles/files/91011724467.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/13f737330da274ef59d1007e0725dfcb/89097972784.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/maviregusuxizogijosirikot.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a270663e4ca---finurepivufo.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/zurawoxetobixijejujek.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608236941806c---siguroke.pdfIn PDF document text
    • http://pitneyclan.com/clients/c/c7/c7afcfad87c307b096642b2e35f52d25/File/xusewo.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/85616096473.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/24098647060.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/dfe4f9d6234f9e71fa52fd0397b6ce65/limop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=plasmolysed+cell+definitionPDF 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_off0000db95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AC 10652 bytes
SHA-256: d4e64dcfa3807a5d7d334b790a3e2e26b8ff2fd56339c55fe082e2894b6f7159
font_02_sfnt_off00010c11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C11 16828 bytes
SHA-256: 6281eaefb9a29d9b98a7230cfc50b602b0fa1f2d0e2d68bdddcb22a23e4f3d1a