Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f83d241341b46f6…

MALICIOUS

PDF

74.3 KB Created: 2021-07-31 19:03:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 239176bf898ab4cec818e190ef338050 SHA-1: d86db8a93fa4e9bc6b3067f7fdf41015545eebb3 SHA-256: 8f83d241341b46f6b01e77753d3ff84abc39db05adf7ad368f45a45b70094122
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and other disposable hosting, designed to redirect users to malicious content. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/f0e19c531ffb730c1b7b55e66e7614a8/68448408152.pdf In PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/u7hi489lh5t7gh581dsjjqhnol/62413477851.pdfIn PDF document text
    • http://cadeco.com/testingsites/advantage_aviation/assets/media/file/rubepib.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/23241282138.pdfIn PDF document text
    • https://coimbatorepressclub.com/FCKeditor/userfiles/file/94390851341.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af9cbd4bbf6---60592429891.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a8905b77222---waverojulenu.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/mbsk478okm66numptjntpbn817/wotew.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/gukitutodekuvidefajeba.pdfIn PDF document text
    • http://samafb.org/uploadfilefiles/zizozexeze.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/24911456777.pdfIn PDF document text
    • https://villatoscana-pi.it/userfiles/file/lorovoxisibumupe.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/d3b3fe94c5c1798908f6bace56f577fa/25890097117.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/22gk7skli4vjgglg5h5oc2911a/33513461129.pdfIn PDF document text
    • http://uci.ir/userfiles/file/27030745141.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/16ff97f13641c4367ff121344d26357c/32297818525.pdfIn PDF document text
    • https://smartcirclegroup.com/userfiles/file/ludajidesaf.pdfIn PDF document text
    • https://egf.tw/test2/images/file/fofelurupaborux.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160d622270c83e---tarofizajaxogamujuvonuti.pdfIn PDF document text
    • https://beytarimcilik.com/admin/editor_resim/file/81558948158.pdfIn PDF document text
    • http://giaoducvietnamtv.com/images/ckeditor/files/80860827505.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb35a4d2f1---tuponosuwor.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/57700004407.pdfIn PDF document text
    • http://bygreenpure.com/userfiles/file/2746474802.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160833cb732262---44355791458.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=frank+emu+maths+class+9+solutions+2020PDF 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_off0000c137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC137 14876 bytes
SHA-256: bf0b285960c4f130aeb961f5a960c3c7b5fe643fa5bb0dad63c06834d16edc74
font_01_sfnt_off0000e730.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE730 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF47 11076 bytes
SHA-256: 51898efbd780456d939fc12764b2423935a9b1439debfcd836a500427aa48903