Malicious PDF — malware analysis report

Static analysis result for SHA-256 933b0406e770f6bc…

MALICIOUS

PDF

76.9 KB Created: 2021-06-14 19:10:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 93cd053b79102967e324f30cf8b84b72 SHA-1: d4a67a6c12c9aaf9dd78f0a04314ecdb5f0dffee SHA-256: 933b0406e770f6bc8f462a1021c70cc703dc745f7d62f9e0602ac46aec8f46d2
156 Risk Score

Malware Insights

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

The PDF contains a link farm hosted on compromised WordPress sites, directing users to download files. The heuristic 'ML_NYX_PDF_MALICIOUS' and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to trick users into downloading a second-stage payload.

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://crewmak.ru/uplcv?utm_term=hello+neighbor+download+gratis+pc PDF link annotation
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acac5e716b8---nujujuviwesuxuzi.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16075c359db192---mujoradofokoguva.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160721f1c54e11---wesegeranonofedapofe.pdfIn PDF document text
    • https://maisonforville.be/documents/file/solidokomeri.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/a17de495944bfe8ec0b0f6fedf27c8a8/14754509211.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160824a67ad10f---busijajila.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16092b28693308---61050373501.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160979ceb41c99---2299159472.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609dfcfcb09af---72642502868.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/ba658ff2ceec3179771e3d4f3d762938/38346588970.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7ae070fdadc79fe322392022474be21b/63929837843.pdfIn PDF document text
    • http://mebco.ru/images/file/jizimalomilebab.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/51lusg9ak30a4hqhjch57j1nqe/85428736737.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/74c3e01d5ea06faaa71b8b663a56e079/45084451655.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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_off0000e331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE331 5316 bytes
SHA-256: b29f109fed23906a7008ce360c71b464937120f5847453284b9ea4f563832c4f
font_01_sfnt_off0000f53e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF53E 10304 bytes
SHA-256: 675f6880476d85a42293d9772a5e74b4e29438b1d71b071c0896a127cafabf0b
font_02_sfnt_off0001183d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183D 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c