Malicious PDF — malware analysis report

Static analysis result for SHA-256 891bdc37fef53233…

MALICIOUS

PDF

77.2 KB Created: 2021-06-13 03:07:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 50262d7a61f833a8d83ef1bfc13b24df SHA-1: e02a95815aaf666e381fb68706bb457c8ad81f88 SHA-256: 891bdc37fef53233cef8047af969d7778162ec609d15eb54acee55beaecbad14
96 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various domains, many of which appear to be compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the link farm structure suggests an attempt to distribute malicious content or phish users. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://pixomot.ru/uplcv?utm_term=piano+jingle+bells+letters PDF link annotation
    • http://kuzfarm.ru/images/file/wamomorekaxebipom.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/91512254313ef427633d1abfe9781ef7/jatupafaxarota.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085abd04cfa4---zikawufizejamafutebe.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f07fa6cac3---defigaxewarufe.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091091a2c161---gajajegitanakotoxonozevux.pdfIn PDF document text
    • https://dietacud.eu/upload/file/powakewon.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/a6d0eda5ad3e34a3bcac8063b87a15b6/92448352054.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/140788c2b5843f0260f23b075f7a9d7c/bemonabipofulixobu.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/d1ca068b39fa57183f99523c104a6d42/70054118195.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/9687350787.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/52414520538.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a6c8a9a8706---1759820710.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/28f73ae4ce9336b5bf85fe2dbe190aa3/78443285513.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/0iu1ql5c88009okbi2877k29gg/92748524488.pdfIn PDF document text
    • https://markeishahall.com/wp-content/plugins/super-forms/uploads/php/files/7290aa638f9a5a93c954823f1885ffa2/mibijirosejaxisejuvabis.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c254a83954e---58012625080.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082f638e529f---xulasoluwudasizid.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef18a63ce0---bugixavuw.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/70a86cbe7fbfc3199fa7449ef37da277/jonisekajetosopejimoxedo.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED8D 5068 bytes
SHA-256: 70581ff6277af58d5ac57e249639fd6944ebf841e6ea2fb274993c2fb35bfad7
font_01_sfnt_off0000fede.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEDE 11412 bytes
SHA-256: 39bbb5467ea37127eb5f044c836439cca6e088fed47d061934930529e0824eaa