Malicious PDF — malware analysis report

Static analysis result for SHA-256 28ab64fd226327aa…

MALICIOUS

PDF

83.5 KB Created: 2021-09-02 18:31:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 54de01b3fe6516767ee20c0ccf520e4b SHA-1: 6c55e8653ccd3755577032fafafdb58f7cbb90f2 SHA-256: 28ab64fd226327aa92f44b57e871a159d9532af6e460b0b8533a9895fab5bcbb
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links to compromised WordPress upload directories and other potentially disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is unreadable, but the presence of these links strongly indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a185a486ee---9188994753.pdf In PDF document text
    • http://allnatureint.com/userfiles/file/8211165238.pdfIn PDF document text
    • https://parokisantolukas.org/Uploads/userfiles/files/97405384662.pdfIn PDF document text
    • http://sujitonweb.com/userfiles/files/24686229640.pdfIn PDF document text
    • http://hotelstrack.com/bot/ckfinder/uf/files/44541148269.pdfIn PDF document text
    • https://mldom.xyz/web/img/podborky/files/33277471233.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/sugowasilofaperul.pdfIn PDF document text
    • http://asorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/63252817793.pdfIn PDF document text
    • https://x-software.cz/data/file/munitarijilazesojoba.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c739ffdcb9f---gixanametabizuzevesukef.pdfIn PDF document text
    • http://haokunchem.cn/upload/files/46139271765.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1610448009ba24---bifenuzev.pdfIn PDF document text
    • http://zonweringnederland.com/ckfinder/userfiles/files/fijefavivizew.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/37100a9e64e0e679c49239033f96d86e/90984830607.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/15386991139.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/32380001233.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/e5ebceccc2f179d4b31bd1ac828515cc/8890690058.pdfIn PDF document text
    • http://michellenevinracing.com/FCKeditor/file/xevodevexiw.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/44057974090.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927917b1625---jerobevisuvomatibekux.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/89491757534.pdfIn PDF document text
    • http://thewellmanteam.com/userfiles/files/96668164173.pdfIn PDF document text
    • https://axlthailand.com/imagexx/files/zojurogivopozujesalefibe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=expository+writing+pdfPDF 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_off0000e44a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE44A 17244 bytes
SHA-256: 9ab7c549bd9ea4e1b24006aa8516f5cac217f9940326cf9860810db5dd63c1e8
font_01_sfnt_off0001104a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1104A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12861 10620 bytes
SHA-256: 2a82c1f09fcd1b07bd5a52cf7720b5bd3d4df396772f30c5fe0668be2fd443f9