Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b6867646b2c526a…

MALICIOUS

PDF

78.7 KB Created: 2021-06-10 04:24:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f6b035b1aaccd390492af4afbf01fbc1 SHA-1: 6c41b8ef5b78f6999884a6cad40a8cf65ca98063 SHA-256: 5b6867646b2c526a429f142c52051e70c718ae31c788f03d31e4b7f11ed2d983
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the presence of external links and the document's structure point towards a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=friend+family+sample+parole+support+letter+from+family PDF link annotation
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb78fbb0c8---84347338066.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/34dddf835813ec6055accfd379560dc0/lagolipet.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/cbb984ba153ecbe65ec0f909ced7d2ab/zodozebolizu.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088e15b22561---54806505557.pdfIn PDF document text
    • http://taskentcompany.com/userfiles/file/nuvozumuduriwam.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/80fc190fce7b603620e6fa9976ebe102/60856160888.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160b93af0f1937---riretusamo.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607145f84fdb8---12943204332.pdfIn PDF document text
    • https://buka.ru/sadm_files/79882511515.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/498787549ddfa066f63e6173aa9f4d4f/vetin.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9983311d4---20983980678.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9de5a88f8f---mabosuxekizutimiloril.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0f69ba90e---37255900131.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16076a79e1ad79---luvuxosiku.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/796636a2665bf4de3de0f8633c6b3715/lofepawo.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF822 5244 bytes
SHA-256: e564a68b65ed4a822dab843388c4db56f8de0b4d0abfd88b9ddfb8b2e93d16ee
font_01_sfnt_off000109ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109ED 10336 bytes
SHA-256: 07972984f2be01ece3caa841f4f370fef7f9de9220f92f830fd5294d1f59466d