Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a33dd4963dc8a47…

MALICIOUS

PDF

82.4 KB Created: 2021-09-11 04:13:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6a3f82d093a8da2b6e4c56a04f2441df SHA-1: bb0f699eb0bec8778887fa66077ca86a4c21c82b SHA-256: 0a33dd4963dc8a47bb4843c59b15bf8338d24dbf53a6f1418464d90cab750f9a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for such links. While no scripts were explicitly extracted, the presence of embedded URLs and the overall structure strongly suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://ensky-chemical.com/upload/files/mopojozadikozojarokakepad.pdf In PDF document text
    • http://moneymaker-gold.de/files/56564510393.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/63493908086.pdfIn PDF document text
    • http://hoaisonland.vn/upload/files/jazenotaw.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/95524005645.pdfIn PDF document text
    • https://www.hkha.com.hk/ckfinder/userfiles/files/11921845247.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f25ba036f---91349788574.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/kijutomomidamedifir.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/xowekiv.pdfIn PDF document text
    • https://eminenceconstruction.ca/viking1/uploads/files/2979350318.pdfIn PDF document text
    • http://brno-skoleniridicu.cz/ckfinder/userfiles/files/robokewezuwowogale.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/fokufituwijuruxew.pdfIn PDF document text
    • https://www.ijestr.com/ckfinder/userfiles/files/16662569545.pdfIn PDF document text
    • http://i-physiology.ru/upload/debusidifesawedifol.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/3lqgiddhr239pitia5teieuef4/rabuxovebimajek.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/30464966811.pdfIn PDF document text
    • http://scandinavia-ex.com/images/blog/file/kazobebakodurunezaporonam.pdfIn PDF document text
    • http://biomax.shop/filespath/files/20210902091009.pdfIn PDF document text
    • http://szpk.hu/_user/file/93279953355.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/torim.pdfIn PDF document text
    • http://copingconversations.com/userfiles/file/14358351492.pdfIn PDF document text
    • http://opuspointpartner.com/ckfinder/userfiles/files/rumupasi.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/wowipoxe.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/wepuvogel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=win+7+emulator+onlinePDF 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_off0000e2a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2A6 16564 bytes
SHA-256: 4283e10cacfddcb93fba9b0f508ee24bdac3ce81c377034ba5782b144a0e1edc
font_01_sfnt_off00010d3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012554.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12554 10244 bytes
SHA-256: 6f7510ca5fd2b5f3a8868481de5cd3bbf4d311acc027fd517d3ad3b59da9d615