Malicious PDF — malware analysis report

Static analysis result for SHA-256 9939f56a3085c27b…

MALICIOUS

PDF

87.7 KB Created: 2021-06-26 16:03:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 31a0764b185006ac304d009584a4a298 SHA-1: 70522bcfadb9edff9e7a138071818525d294439c SHA-256: 9939f56a3085c27b057356168d13d27d6716739d15f2c2dc9e1da847a9107ad7
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains a large number of embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the embedded links and the 'link farm' heuristic indicate an attempt to lure users to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077043729846---sulevilogowojezarug.pdf
    • http://beamstraffic.ae/amb/userfiles/file/giwumu.pdf
    • http://ghhs1968.com/clients/5/57/5762190d0a265df614d1f295a7060a42/File/baworufet.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/4a9e97d2ba435dac7f9dbc2adabbb8cc/dupizazojuvisagemuxi.pdf
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/5adeb53a3f4e0be330813fdf0d861bbf/59292851023.pdf
    • http://pelesiuvalymas.lt/i/File/25885549494.pdf
    • http://vdadanang.vn/app/webroot/assets/files/79769588856.pdf
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/cc633676c67b8ffd49b441ae21d3cebb/sufukavizinizav.pdf
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/84e519a4d8eec7e60eb23e1d1a4e13b2/zemepivejefakamej.pdf
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/916a671ef7f3065359b114b54e040c3a/pabekepipu.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/99p2t76it7s18cqnqcttv8jo5d/37274554857.pdf
    • http://animalscipublisher.com/files/upfiles/file/56008382966.pdf
    • http://dynamic1984.com/user_file/file/fefotodidubalulev.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b7c89b329---42565601784.pdf
    • https://binarbaidservices.com/public_html/userfiles/file/91606293801.pdf
    • https://sheenabusesandcoaches.com/userfiles/file/1361108031.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/baf7c99f722a210f30635cdd7efda1d5/45419514591.pdf
    • http://bouncebodysupplements.com/newerac2c/userfiles/file/lomazevikoruxurag.pdf
    • http://hzbmsj.net/images/upload/File/rutebaperenuwupovikod.pdf
    • http://bjhtdszdh.com/v15/Upload/file/20216101728172803.pdf
    • https://vieclamxaydung24h.com/upload/files/97170579272.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f28d167a54---taxopoletikeba.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/9eab0c853679a0528c893b5d1d51444b/72840508373.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16088649b2ecfb---nujajamexutelasiragalite.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+cheat+on+a+proctored+online+test
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f457.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF457 16792 bytes
font_01_sfnt_off00010c69.bin
e874adb6f3289e67c3541a8c67b2792c62ce7f0fe3563812c03672e790002ee9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C69 17180 bytes
font_02_sfnt_off00013907.bin
e178fde3589c73524e2acabdd13a1a946c22aba77e93fec895b9922ecf976334
pdf-font-stream PDF embedded font (sfnt) at offset 0x13907 10688 bytes