Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac202824e773eb28…

MALICIOUS

PDF

70.5 KB Created: 2021-10-05 07:43:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4e0e41135a23696c21d4d60f5173f4af SHA-1: b61d974c69ab3d1630725a14e19517b4a7e20c90 SHA-256: ac202824e773eb28db9bfbbddb0b193486333a94cc66521331e8abc22ba733a9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to PDF files on potentially disposable domains, suggesting a link farm or redirection mechanism. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating the PDF is used to create a network of links on untrusted hosting. While no scripts were explicitly extracted, the nature of the embedded URLs and the heuristics suggest the PDF is used to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oferta.lt/i/File/12616749747.pdf In PDF document text
    • http://problemconsulting.com/img/download/files/siguve.pdfIn PDF document text
    • http://flyingfish-stay.com/userfiles/file/xoregitobozudo.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615abb8fd98ec---59179658226.pdfIn PDF document text
    • https://ekransamara.ru/files/6001315203.pdfIn PDF document text
    • http://byecook.com/ckupload/files/13728837899.pdfIn PDF document text
    • http://discus-rus.ru/upl/file/92252156385.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/vafixuxesuwenan.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/talomenifosegipar.pdfIn PDF document text
    • http://ancheng-medical.com/uploadfile/files/tulokexobojaloxupexufut.pdfIn PDF document text
    • https://kotypsy.pl/ckfinder/userfiles/files/fovizes.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/sepiwapakapovez.pdfIn PDF document text
    • https://hediyelikhanem.com/calisma2/files/uploads/vofatotumitel.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/91712591268.pdfIn PDF document text
    • http://sinoorchids.com/image/file/burusef.pdfIn PDF document text
    • http://e5tbr.alruaa.com/ckeditor-ckfinder-integration/uploads/files/89654976046.pdfIn PDF document text
    • http://agama-rc.com/upload/files/midedajexeronesimijati.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/67296039998.pdfIn PDF document text
    • https://mkontakt.com/dat/file/76855396946.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/29886991905.pdfIn PDF document text
    • https://music-group-store.com/upload/files/56947322679.pdfIn PDF document text
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/tenifofexumubut.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/f029cf3b259eef3f2083038970ed9cfa/laligizo.pdfIn PDF document text
    • https://copacndg.com/images/uploads/files/fubagevunatipunuler.pdfIn PDF document text
    • http://npi-management.org/ressource/site-image/files/48631990971.pdfIn PDF document text
    • http://sanalights.com/admin/admin/uploadfiles/file/kuwidukuwogedubikup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=is+moving+water+renewable+or+nonrenewablePDF 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_off0000b5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE07 10692 bytes
SHA-256: 226f04dfc5fbd7fbd0dcdd76038499218ebd719f9024909e74441fa9f593e91d
font_02_sfnt_off0000e690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE690 14940 bytes
SHA-256: 5dd655441367c7a0f242b1855a4b8b501b06495879c9938cdd0f66d86d077274