Malicious PDF — malware analysis report

Static analysis result for SHA-256 79fd479a3f810ad1…

MALICIOUS

PDF

70.3 KB Created: 2021-06-15 19:05:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: c3d0b18f44fc17750e7ccfc696bbf097 SHA-1: d8e90f32d1108274cc34d524b1dde4525319a9f3 SHA-256: 79fd479a3f810ad15b930e9fde321e965e5c1634d4af428303a6778b0d55cc83
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various websites, many of which appear to be compromised WordPress installations or disposable hosting. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, suggesting it may be part of a larger phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://archism.ru/uplcv?utm_term=lyrics+there%2527s+a+tear+in+my+beer PDF link annotation
    • http://allprintusa.com/admin/images/file/50563833732.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b25ec89feae---16100696198.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607a60540729b---tevekojipovisaxepelug.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160894113df354---rubal.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/16099b229596a8---42852767518.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/gp1d3er676fsrrpgp0s9a10vo1/20957540921.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/f7bd588833e52a085384b195627da116/32880981110.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/c9cf6e5a058f5303966e8275720e048e/riliwikajuwowagi.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/f22f303599f6d5c9543fde5a70b96416/xebaliletad.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a7463c61168---16100601239.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073397752a1d---11490325852.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/a730a7dc998262777b45060ffa895a7d/27938543742.pdfIn PDF document text
    • http://cunningham-reunion.com/clients/7/73/7399477c88ef979e1ad3ac38e42cffcc/File/83309868398.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/02abde156159ffa580b38fadca39f9a9/43964536838.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_off0000d54e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD54E 5224 bytes
SHA-256: 9d5d675dc4393ec661b882658f680e70060ede11bbb74b42db4ebadeaac085a0
font_01_sfnt_off0000e6fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FC 10936 bytes
SHA-256: 54e2858da83dbb8e1d2197c653dba77d98bede79f22d524eaf0cd4b3706d015d