Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a636676657d4c0c…

MALICIOUS

PDF

73.6 KB Created: 2021-09-24 22:03:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7703231cf57e9336c650c7a5c70b543e SHA-1: 8fa45118a29a1cb330617716fcb1b446c06e1682 SHA-256: 7a636676657d4c0c2b17100a1718d16d54af1ddb3d8f612d68bd864800ce9647
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to various domains, including those hosted on compromised WordPress sites. The presence of external URIs and link farm characteristics suggests an attempt to redirect users to potentially malicious content or phishing sites. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://crysiq.ru/uplcv?utm_term=the+walking+dead+season+1+hack+apk PDF link annotation
    • http://minuspk.ru/minuspk.ru/userfiles/file/44242776777.pdfIn PDF document text
    • http://propack-th.com/image/upload/File/zulefosegamufojako.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/rinepesiwixewafujefa.pdfIn PDF document text
    • http://wellfoto.cz/pictures/files/84057211762.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/4140820899.pdfIn PDF document text
    • http://stonepigments.com/userfiles/file/90123191414.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/c11d038ee253cc366a55dc58e854ea00/zodawofefimawimapeki.pdfIn PDF document text
    • http://gabinetortodontyczny.eu/userfiles/file/44891587461.pdfIn PDF document text
    • http://www.og2c.com/images/file/wanafas.pdfIn PDF document text
    • http://archi-m.ru/userfiles/file/6967308516.pdfIn PDF document text
    • http://poliinc.com/upload/files/82163154877.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/2667029253.pdfIn PDF document text
    • http://reanda.com/jingkelun/userfiles/files/20210908161747.pdfIn PDF document text
    • https://service-panev.com/userfiles/lofijoxenirozafuwimifew.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138255d28057---92776443487.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613944cea1d17---16749359621.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/51023299310.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/67529154121.pdfIn PDF document text
    • http://mediacast.vn/ckeditor/upload/files/nulaguwujawix.pdfIn PDF document text
    • http://www.jokilaaksonratsastajat.fi/file/ginijajuludawinezegalag.pdfIn PDF document text
    • http://thewesternmist.com/userfiles/file/totarilunamevilusimonur.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_off0000b855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB855 18188 bytes
SHA-256: 03e48d792c40d63b221e4239699001dd4fb82fa8ca05c0f10ae4f71427be73c4
font_01_sfnt_off0000e801.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE801 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10018 10788 bytes
SHA-256: 2d83e96f9d38fbac84d30051906d8a2474b3776d1e30ec6268cd89dd9c93f8fe