Malicious PDF — malware analysis report

Static analysis result for SHA-256 a11fbb5d9c2b975d…

MALICIOUS

PDF

74.1 KB Created: 2021-06-17 20:20:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 11682deba981a0098bfe96c117708b3a SHA-1: d8ff0e57b3ed2d6a6f7e38e1cb655b510f2ca56f SHA-256: a11fbb5d9c2b975dfd9d1f6178d99746deec63fc543cbb326216a44c74d3775f
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 CMS upload directories, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a phishing lure attempting to trick users into downloading further malicious payloads.

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 http://barcabianca.eu/upload/file/53625577815.pdf In PDF document text
    • http://bualuang101.com/backoffice/upload/files/95508450753.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608d7a33cb98a---50885648023.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e1a91c3db---15333308357.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/1e87b85bf0d51fe47bfa6117292d3fad/rewubevaroxuzen.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/xixaromumowa.pdfIn PDF document text
    • https://www.colours-of.com/wp-content/plugins/super-forms/uploads/php/files/uaheg7hi3a8lohvdbh09u6vv7m/vovanogorawuwunuwe.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/vonejelasavejinul.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/b32ce26144c9e934b2d5be07f7753dd4/zuwoxizifopukamajosete.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/rujuzin.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160725e1b21e7a---69162498318.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/955097b49b82a2e9bd5fad94f7a8a230/foletererilonuve.pdfIn PDF document text
    • http://bdn10.cz/files/file/47598864409.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/52274913626.pdfIn PDF document text
    • http://wami.cc/data/files/90197625325.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1609a1fb213da2---57787711674.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=guardians+of+galaxy+full+movie+downloadPDF link annotation
    • 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_off0000e0bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BF 5580 bytes
SHA-256: e75fa5cd5308aaeff112fdc9d143806658d3e271f703db21214aee73b1c5d429
font_01_sfnt_off0000f3c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C3 11756 bytes
SHA-256: 3eb001baee8229a21d5950b58e18d657a7ca6d2847369736fe18eec609c92e43