Malicious PDF — malware analysis report

Static analysis result for SHA-256 2cb36bc60090a272…

MALICIOUS

PDF

92.5 KB Created: 2021-08-16 16:41:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 290995ff71bcbf408374d217f647af79 SHA-1: b189deb172ab70fea0f25f10374c9d5b2fd28b1d SHA-256: 2cb36bc60090a2725a155c5a535c01d59482fc445079a29b930a0630a9ccd7d1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/96178017209.pdf In PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b633835a65---gusasirumol.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/3e0419d392641fad92ad13d3269f6927/daxukapubipoxowapurag.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/41615452366.pdfIn PDF document text
    • http://qqsbg.net/uploads/file/3658210393.pdfIn PDF document text
    • http://mawaevents.com/uploads/file/zazabawonebe.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160dcab7b6eaac---megebadele.pdfIn PDF document text
    • https://longhoang.vn/upload/files/pizuxegegikedu.pdfIn PDF document text
    • http://iccarrentals.com/files/file/49400931181.pdfIn PDF document text
    • http://btc-ltd.com/upload/file/kenosefiverekexili.pdfIn PDF document text
    • https://www.e-oswiata.olesnica.pl/ckfinder/userfiles/files/sizeru.pdfIn PDF document text
    • http://simmsfamilyreunion.com/clients/9/98/98d47f1658d09d39d77ba56043454c9c/File/9256807720.pdfIn PDF document text
    • http://ohsclassof73.com/clients/9/9a/9a21b0b253f7c4eafe662346d237c286/File/kajujebudidarifabejaja.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161168ff01e20d---14490735685.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f926da00f2---bavebe.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/uor8p8sti88jlmcbqjdmabud0d/66607819397.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608d61574adc0---jizonekot.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607e17490751c---xevegetizubojakegiwape.pdfIn PDF document text
    • http://www.heksan.com.pl/file/sogetuwedeb.pdfIn PDF document text
    • http://ayurvedicclinic.org/userfiles/file/58639879272.pdfIn PDF document text
    • http://kccmaul.com/files/files/masibuzukugifalotukavesa.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe6bc395c4a---totekezebuv.pdfIn PDF document text
    • http://ipceurope.eu/assets/file/293935818.pdfIn PDF document text
    • http://hyundai-dongdo.vn/images/files/dejejefuzavabajigijifomop.pdfIn PDF document text
    • http://sodrex.pl/userfiles/file/tufafizitageni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+fix+toshiba+tv+that+wont+turn+onPDF 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_off00010397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10397 17876 bytes
SHA-256: aa9d3404522991bba49fa8e6c7cb328df4192b44f66cfce8875b7245e7323787
font_01_sfnt_off00013293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13293 10616 bytes
SHA-256: a6565994765a7deebf1624023e0163bbe2b64302b624e22e73975311e04b2fe3
font_02_sfnt_off00014ad5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1