Malicious PDF — malware analysis report

Static analysis result for SHA-256 676c66270d55cc8a…

MALICIOUS

PDF

88.6 KB Created: 2021-07-17 01:06:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b3b8e4c8b0ccf63d4899bd679e865df3 SHA-1: 82e0928de02b3582c18298372db4196f2e3fbdca SHA-256: 676c66270d55cc8a9cab0949291e966dd9ea73c240ca7e6b1be29b00525befcf
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1070.004 File Deletion T1553.005 Security Software Installation

This PDF file was detected as malicious by ClamAV and exhibits multiple high-risk heuristics. It contains a link farm pointing to compromised WordPress uploads and instructs the user to disable security software and install remote support tools. These actions strongly suggest an attempt to facilitate unauthorized access and control of the victim's system, likely as a precursor to further exploitation or data theft.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 9

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16083cb00aedd3---81486039566.pdf In PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a0953299098---2554551694.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/bozerisatobim.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/2c3634ac1d198e37a8ab8d5d7ee9b5f9/73229939303.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607db9d837b55---18189838481.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/4047f37f03b3a0105be6e205a1a6b0fb/jozegevifekamimepud.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/desobaxojo.pdfIn PDF document text
    • https://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/939a651b24dc36321aa50bb53eb348b1/ramebolemudurufuka.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a238a7624f---parovanasumakadewepopum.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d7456f8ab---3649782625.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/9243613579.pdfIn PDF document text
    • https://aurorabersinar2.com/contents//files/25170747996.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16072e3928976d---92296889596.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/35403315681.pdfIn PDF document text
    • http://ipsgroupjjn.org/userfiles/file/rawevomivanivanoliku.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/05f7481e30cf1cd1b2e98d3b0fa5dba8/kukegosawopunutax.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/98c4c1cb6acfcc8e507b49b29a48119a/xeraxesezibajepipa.pdfIn PDF document text
    • http://55thocscompany.com/clients/62662/File/85555697258.pdfIn PDF document text
    • http://famillespourstarlight.org/clients/a/a9/a9b42c05011d3bb27e7f7ec2ed30324f/File/romukizepugudejisalimovu.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/ed13ae968e5f14b1114cfd546c144d9d/riguzagereposojik.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608521a00e3f5---5429404949.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/7efd0ef1addc79fc89c05b87f9f19b7b/21123821407.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/a38df49249f51d39579648d3481ceef8/wanokivomudabez.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=license+manager+is+not+functioning+autocad+2019PDF 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_off0000e8b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100C8 11292 bytes
SHA-256: a19824dc481ba3ed5dfe830583d2d66e8683badadf0a6596ac61a50e2b77c6a1
font_02_sfnt_off00011b31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B31 28320 bytes
SHA-256: e29bc61c6b3f72e2c7a6a0fce77f7073842ad304ad9c2cc82d161bfdaae3974b