Malicious PDF — malware analysis report

Static analysis result for SHA-256 61e13c96ce1fb28b…

MALICIOUS

PDF

84.6 KB Created: 2021-09-12 15:45:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ba1c6a0828725f146d514e2ee404da2f SHA-1: 0896e60df0ef2f5e22b301f612c31287aa183bfd SHA-256: 61e13c96ce1fb28b19ea5414e4610484604101387146f084f9a57d25b65c1d99
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. The embedded JavaScript likely serves to redirect the user to these malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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 https://inwebjor.ru/uplcv?utm_term=redmi+9c+setting PDF link annotation
    • https://dolphinsolutions.net/ckfinder/userfiles/files/mobaremopoxorukika.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/c4ce27f8d30a40dafb29a364b3d8fbef/birawudoliz.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/tuvijegosaba.pdfIn PDF document text
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/62487672378.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/14228822445.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/30237012505.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/zogilenerabuwumozoturil.pdfIn PDF document text
    • http://hoanggiaphatstone.com/upload/files/97838374551.pdfIn PDF document text
    • https://www.orthovision-lublin.pl/ckfinder/userfiles/files/wamakugejedaremizuduvo.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/medegesedewat.pdfIn PDF document text
    • https://wildarium.com/ckfinder/userfiles/files/jejivakuwemubosubaminujul.pdfIn PDF document text
    • http://piannocreativo.com/js/new/fckeditor/userfiles/file/nobamorag.pdfIn PDF document text
    • http://koala-al.com/d/files/1122969466.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/d32453988d7170a966f939b1a1dd5093/zolexafot.pdfIn PDF document text
    • http://voyagevietnamlaos.com/hinhanh/file/96689854689.pdfIn PDF document text
    • http://hidrometa.com/images_upload/files/57049029475.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/nipabuwiraguluvogo.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613d4eb14f627---weguwemud.pdfIn PDF document text
    • https://tlproduct.com/userfiles/file/zikugefoxo.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/161310891705e8---kesaretipibi.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/2003939844.pdfIn PDF document text
    • http://eternoohydro.com/d/files/18393927666.pdfIn PDF document text
    • https://rireenfrance.com/images/upload/files/85175008754.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/36279583867.pdfIn 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://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_off0000e82f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE82F 10496 bytes
SHA-256: 8b2c9e592a40cf57199b3af465e203db5ba7cba8cd75892c5c2ea708c3cb506a
font_01_sfnt_off0000ffd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117EB 17428 bytes
SHA-256: 5a4563dd9c854ca39ab3c6179e947b27904dd11f873ffe1c786ad19320f0ae1e