Malicious PDF — malware analysis report

Static analysis result for SHA-256 83bfa8d41fe7f4f6…

MALICIOUS

PDF

81.8 KB Created: 2021-09-12 08:59:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e12e1740cf66446512d56e6dad2c0190 SHA-1: 2cd0541e57df9dae49e68e3c32d47da2780e45e0 SHA-256: 83bfa8d41fe7f4f6b18697fa5bf7614f72972e0e646d8b519343980dff5277a1
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a link farm designed to redirect users to malicious content. No scripts were extracted from this sample, but the structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://alvit-bk.ru/userfiles/file/9754997225.pdf In PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/8916606435.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613267c56e725---mijavavaze.pdfIn PDF document text
    • http://solentpodiatry.com/jackvl940/web/content/images_uploaded/file/86021648578.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/gupilabefer.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/23934a81eb7404f52e4e029fe80415fb/bogig.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130e5cde8fac---kujopojotunojoxobapaw.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/s23rt34e2b371879fl3114j8t1/zulosanupimanaladokovanib.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/73264130407.pdfIn PDF document text
    • https://treasurehunterdetectors.solar-ovens.net/ckfinder/userfiles/files/60432009866.pdfIn PDF document text
    • http://fsf-vastroad.com/userfiles/file/35908450363.pdfIn PDF document text
    • https://hirurgija.me/files/17858851583.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161344e2f8185b---82680087593.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/dozem.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/18176735110.pdfIn PDF document text
    • https://eastmanllc.com/ckfinder/userfiles/files/lejokipilif.pdfIn PDF document text
    • http://morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613449612141a---taxizezofupude.pdfIn PDF document text
    • http://andreaslasnik.com/data/files/revijo.pdfIn PDF document text
    • http://phamtrangia.site/upload/files/87241617616.pdfIn PDF document text
    • https://actionsporting.com/userfiles/files/12378743345.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138fc282d445---diferemexozames.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/b6ce430ce370185c9d120ba5e8bc7937/nuforixid.pdfIn PDF document text
    • http://kronospan-mofa-hungary.hu/editor_up/rexotuwoxagud.pdfIn PDF document text
    • http://zjbfjt.com/upload/files/3414863451.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/bilapiwamakubom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=como+puedo+actualizar+mi+celular+androidPDF 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_off0000d85e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD85E 10696 bytes
SHA-256: 36a4728654b426a3f643ff9f44ea2ec89dee3a04c2da17f95375ede74f8105c8
font_01_sfnt_off0000f0e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E0 19104 bytes
SHA-256: 635afdbc7742f82f0c9ecb589b7bbab2169def92cfa53631f7ed31cdf65a7e30
font_02_sfnt_off00012104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12104 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1