Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a97cbcdab7f8e63…

MALICIOUS

PDF

89.4 KB Created: 2021-08-10 15:54:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 759ae8553f0072e1823f90ee925fbff9 SHA-1: 90c570bf83c7f4e14c6ea84c5a963398a3c1ec7c SHA-256: 4a97cbcdab7f8e6399a888b739001416907341416796d72d182a22f5fee74ab2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. Heuristics indicate this PDF functions as a link farm, likely intended to direct users to phishing sites or download further malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

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://garglob.ru/uplcv?utm_term=resultados+becas+primaria+2020+estado+de+mexico PDF link annotation
    • http://aksaaydinlatma.com/img/editor/image/file/89546591183.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/1312797613.pdfIn PDF document text
    • http://kcde.kr/userfiles/file/1858797506.pdfIn PDF document text
    • http://graham1978.com/clients/79565/File/xomofozegodeveresalafepa.pdfIn PDF document text
    • https://a5productions.com/home/a5pro/public_html/ckfinder/userfiles/files/16295676786.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/33917055788.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095fe0ec1342---11828991247.pdfIn PDF document text
    • https://e-tta.com/app/webroot/userfiles/files/gugumo.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160809e9ec5be9---38037449852.pdfIn PDF document text
    • http://xn--80aab8aioy.xn--p1ai/userfiles/file/77323441889.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160aacd287fee2---9906172875.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/71370637150.pdfIn PDF document text
    • http://irishvaughans.com/clients/7/7c/7cfe0b8ff6d5e3136a6575a9b258a09c/File/19001393725.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/45589647312.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/pikaba.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b284853a1b7---roxidaxigegawobomir.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6b1e04c73---58305911587.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/acb594e72fd1ccdbe41aa23e98bf3060/92327928067.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/5msohibc4cq7ufjuaibb8sg3r0/vudizev.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/8562177178.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/jipimaponujojuwutemixivaz.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/79ksuo4ba6vlpnuo92jsthijur/folajikebalularafevo.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/40245041924.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/21702075435.pdfIn PDF document text
    • https://travelsafeway.com/userfiles/file/11360416574.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_off0000f028.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF028 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001083f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1083F 11200 bytes
SHA-256: aadb8742fb29a57b8210cadeb28556a6f02cff75851eb17ce0b78d8f59814b6c
font_02_sfnt_off0001224f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1224F 19588 bytes
SHA-256: 37ebfbd23dc3f14af5d3fc7e3899155025d357cab979ac385989e42d2981749e