Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8efa88918675b27…

MALICIOUS

PDF

84.6 KB Created: 2021-06-11 03:15:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 1ee5da9761e3e8c8bbd1f6217734e70f SHA-1: 5996a572643cdfaaa00333682f4763823f700175 SHA-256: a8efa88918675b27a2bb7b26507c247b864dc9185f1184f0111c4ea83b0e3edb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link farm pointing to multiple compromised WordPress sites, a common technique for distributing malicious content or phishing lures. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://krisoc.ru/uplcv?utm_term=icloud+activation+lock+removal+tool+download PDF link annotation
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a090e574118---83843509737.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/9548fb4a7d484bb3933d32026ec45cd6/xajugazifugokisanugune.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/3uus107ss1mss0jisag0duss61/divakoxoxeponex.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070109887093---xilokelu.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160ad666c2c479---zopejetavoxujob.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1609efeaf54ed3---53991334078.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/fabef5f9ed235a781d5945216c6180ee/19623108401.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/2l7ig4uk46s7efvjqmnmhgd251/negekibibubozokekifonaxam.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609831f11c1fd---20214136293.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/a4877b2d978b97c2b91b21d442531498/kedopigofesuxopaganul.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/21ed221a245bd065ab039e4942c4c9a2/53510748019.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/dbf955695c1bcfde432775bf461f453b/63521113235.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/euq665uvr9sbm0upl4dkqan3r9/pedebefotutanez.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000102bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102BD 5060 bytes
SHA-256: 7f97cf9d875795c6f9cea5068d784bddf588dd23b993b7a50ea9844871292636
font_01_sfnt_off000113ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113EC 2228 bytes
SHA-256: 244710ac342229bd828c68d5a8bf297d36908c21c9458e035d91ab3394502ce9
font_02_sfnt_off00011de6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE6 11532 bytes
SHA-256: e04d347b2cb5792d580a97452134f1ca183e08e70083a4272d63e5225a8616e3