Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdf4acbb8d489020…

MALICIOUS

PDF

85.0 KB Created: 2021-09-08 02:31:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f3c7b9edc8c2892dbe8b4b04dd47ab76 SHA-1: 653e2221f543b19ca5a316e75b6310846ae129b4 SHA-256: cdf4acbb8d489020bca4d0fedd15e87729cd721d8c4389db771b81b88f54ad40
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by ML classifiers and ClamAV. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and the presence of multiple external URLs indicate an attempt to lead the user to malicious content, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://pistant.ru/uplcv?utm_term=fca+cass+handbook+pdf PDF link annotation
    • https://coopinproject.eu/ckfinder/userfiles/files/jejifudamokozidi.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/22156031377.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/14577499769.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd1b8d4575---figawudidajavemozorixugo.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/kowigimesuf.pdfIn PDF document text
    • https://kuni.ro/app/webroot/files/userfiles/files/fanowoti.pdfIn PDF document text
    • https://megatekspb.ru/sites/default/files/uploads/44684966788.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/tuwivanogimawuluxerore.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/0817850b7d6d8ab763f5ca0d7b4de685/52747512586.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/adffcb216dcd763e2960db16cbd527c0/79727711963.pdfIn PDF document text
    • https://msiutilities.net/documents/40486090150.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/6ab357ab0f70ad4ee302d95bd4ea12b5/jozopukapukilazutofijib.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/jowifapodemod.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607463cc5d3de---38999649130.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd14fb6331---11965354924.pdfIn PDF document text
    • http://fritz-fahrlaender.ch/download/67889793393.pdfIn PDF document text
    • https://greenvision.vn/hinhanh_fckeditor/file/putapeduledijex.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/fucc14u6b6huqaj5onvnc047n7/fizafefajisizidunomeja.pdfIn PDF document text
    • http://119hero.kr/userData/board/file/luwuzebigiwadez.pdfIn PDF document text
    • http://kammatrans.com/userfiles/files/98580968480.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/39f6e25287fadaa610bf0c2efe57524d/derusadaw.pdfIn PDF document text
    • 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_off0000e8e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E8 10460 bytes
SHA-256: f9b703d8f2c91c9f8ed5ff7a236ee6c86cf801bf02924088bb4f2be9fe3c4a60
font_01_sfnt_off0001004f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1004F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11861 17944 bytes
SHA-256: e380b53f27d3923c64f72f85b4a7c36a9fca9a19745891dffe52f2372c6a7936