Malicious PDF — malware analysis report

Static analysis result for SHA-256 536b91e1ee0912e3…

MALICIOUS

PDF

83.5 KB Created: 2021-06-14 12:35:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: be56258351ad392c0c294e5754698f7f SHA-1: c2687281a721e2be8b729065c0f624a4f6d4bd8d SHA-256: 536b91e1ee0912e3fdbb6d8ba70b37434052e8f1b7597408931f59e324bdd169
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a phishing or malware distribution campaign. The document body, though obfuscated, appears to reference software keys and download lures, reinforcing the phishing pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://allytemp.ru/uplcv?utm_term=10000+reasons+original+key PDF link annotation
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/31dbe46f731ce9a3675811e9dbb8c63e/67808714758.pdfIn PDF document text
    • http://controldellaves.com/app/webroot/arxius/file/silib.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/38ba761d0a8c11e6406d9f8aea7fe3d8/zumoxezunusivimaje.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078455083660---gakopugik.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/oa2v6noen4jeu110glftqburi7/66167797808.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/4bda19bda18b1dc748484f433a2bdee1/visevuv.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160afb681c9ee6---petosagavalitaxuma.pdfIn PDF document text
    • http://sl1971.com/clients/5/51/517263f0417f9379c67e6eba0e0bdfe8/File/94757970473.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac0cdbcc8d---betasagariwu.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/80382920646.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094ba437af10---karanopi.pdfIn PDF document text
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/34b9ea9dccf89dcf6d0d107a617c4784/vamijemule.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/470aaf2efa1ccc62ea8ba1325a0477a3/99657436584.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0012a77fd3---wupafiponovurinuxiki.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/dcbc0d18eedd4d763cf712f95af89a6c/lemejowagidexulokixodixa.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1609c702d19474---bogabesuxuvavetas.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_off00010aee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AEE 5120 bytes
SHA-256: ebe95dd66f4548a2b65414c5f573908af339f5f0bed21aa7492f086f626eea00
font_01_sfnt_off00011c76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C76 10664 bytes
SHA-256: e49a4854db01d270ee8383a39cf01911ca4e26fb80b84c37cb6e3144118dca5f