Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bc9a2b63a30739a…

MALICIOUS

PDF

85.6 KB Created: 2021-09-21 07:45:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ca1146a75a510a44f04e588b30d94764 SHA-1: 036dcc6c4393e8af5c965f41d1d3bae6dee44c5e SHA-256: 8bc9a2b63a30739ac95ded9d0349fd09f648124039fb0565af1eeb993982c8d4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://inwebjor.ru/uplcv?utm_term=tenet+movie+online+watch+now PDF link annotation
    • https://machnik.net/ckfinder/userfiles/files/43770394170.pdfIn PDF document text
    • https://unicorn.mn/js/ckfinder/userfiles/files/zetufefi.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/fapetokugirufil.pdfIn PDF document text
    • https://ymy-tea.tw/upload/files/rafeforemukuwilubimi.pdfIn PDF document text
    • http://wuchem.com/upload/files/gudezawis.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/paposikelajoletev.pdfIn PDF document text
    • http://mgbig.com/upload_fck/file/2021-9-12/20210912052756245308.pdfIn PDF document text
    • https://registracijakoncar.com/webroot/js/ckfinder/userfiles/files/nolap.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/16531254575.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109021653284013.pdfIn PDF document text
    • http://cheniou.handysociality.com/upload/files/42044735963.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/f31e3223685cf79c1b97ca8e79cf6c04/12491140884.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161445961f2b75---60501917150.pdfIn PDF document text
    • http://photonart.nl/phpcmsys/file/vuxepebav.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/161460be904a0b---87469719662.pdfIn PDF document text
    • http://borisovhlebprom.by/var/upload/file/diwakopukovorisilitesizof.pdfIn PDF document text
    • http://gaestehaus-am-erlkoenig.de/img/editor/file/66282431790.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/39266705935.pdfIn PDF document text
    • https://e-motorcycle.tw/upload/emotorcycle/files/96760874686.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210921004201666445co1pa6.pdfIn PDF document text
    • https://10playsolutions.com/clients/softklk/documents/_articles_/file/fadufunitale.pdfIn PDF document text
    • http://canhtoanland.com/upload/files/4963353245.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_off0000e35a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE35A 10340 bytes
SHA-256: 0e0d766e6c630980cc61121d940a0bcf794d5b7bfa7f762ee673851141b4d9da
font_01_sfnt_off0000fa91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA91 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000112a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A3 19904 bytes
SHA-256: 85dea04724967844eeb6a1be9a04e9eaa32f4336ab1fcb7bcd8e0b9444f8b9d1