Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dccc0d259eaf79c…

MALICIOUS

PDF

68.9 KB Created: 2021-09-19 21:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 11e35e55a45577c9bfe3a3af6610aba3 SHA-1: 997e4a6ab388184598ac257e4ffe4d7efaf5ac63 SHA-256: 8dccc0d259eaf79c9cf6f7592f388bcff57870eabb77c4b146249fb8e93cbfd3
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external links, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to exploit vulnerabilities or deliver further malware. The embedded JavaScript is a common method for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ktcz.eu/files/files/solidanaxewov.pdf In PDF document text
    • https://awinresource.com/uploadfile/file/dimogobot.pdfIn PDF document text
    • https://ice-group.pl/userfiles/file/susot.pdfIn PDF document text
    • https://aljuboori.com/userfiles/files/70669445888.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/pqo1g84401hjmpcs1gv5eboq43/dexebisisipeneraveru.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c0afecd98---72598872695.pdfIn PDF document text
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/12759531700.pdfIn PDF document text
    • https://onderhoudnlgarantie.nl/upload/file/tibuminawuvitakenuzive.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/fumuzatowisusomebitubuxek.pdfIn PDF document text
    • https://xehowo24h.com/images/ckeditor/files/76271551626.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/juxatujizu.pdfIn PDF document text
    • http://playoz.com/ckfinder/userfiles/files/28933307848.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/1408019580.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138f100b0632---93201881327.pdfIn PDF document text
    • https://soechi.com/userfiles/file/giseno.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-09-16/images/files/49760070482.pdfIn PDF document text
    • http://tochuchoinghi.org/files/runofatipuk.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/nolaxexivu.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/lililu.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/80741799872.pdfIn PDF document text
    • http://cristal-in.fr/userfiles/file/49201031819.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=google+nexus+7+tablet+reviewsPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000affc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFFC 10864 bytes
SHA-256: 794e9681a0e4ff8e75f11df3e99266517c3a721c9bf0cfc50dfa09ea7f4340e4
font_01_sfnt_off0000c969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC969 14488 bytes
SHA-256: c3055ded16e19699442068fb5291698e75b70053e508e3d1d7a9f24fcb57141e
font_02_sfnt_off0000edda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1