Malicious PDF — malware analysis report

Static analysis result for SHA-256 dda400761b0e0793…

MALICIOUS

PDF

75.2 KB Created: 2021-09-25 08:08:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: dfe1158185922fee3540d317e8c1308e SHA-1: 13b45e87108d5298e0b660f16acba74c146077e9 SHA-256: dda400761b0e079363fca94285d0c1089426817f461bcf252b39f3fe36a9aba2
126 Risk Score

Malware Insights

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

The sample was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The primary purpose appears to be directing users to a collection of PDF files hosted on various domains, likely for SEO poisoning or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://royalgoodviewresort.com/Uploads/file/rubojeramezusadaj.pdf In PDF document text
    • https://hoangphatdanang.xetnghiemadndanang.com/uploads/image/files/69754865909.pdfIn PDF document text
    • http://locthanhroyal.com/upload/files/vilapuvabibux.pdfIn PDF document text
    • http://volker-issmer.de/userfiles/file/11884186707.pdfIn PDF document text
    • https://wineuniverse.us/userfiles/file/99287819018.pdfIn PDF document text
    • https://dallaslandscapedesign.com/media/files/sixikomu.pdfIn PDF document text
    • http://csc0516.com/userfiles/file/20210920175214_y71h4k.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/caf350c9a7650b8116059615d36f0ba7/gafexefol.pdfIn PDF document text
    • http://fitviewer.com/files/file/butuwafevuxusigisuvubos.pdfIn PDF document text
    • http://hyundaihungthinh.com/uploads/images/files/46410808820.pdfIn PDF document text
    • http://hoaisonland.vn/upload/files/bitozejexovefikogew.pdfIn PDF document text
    • http://balaton.varosom.hu/userfiles/files/lawovosutojusagetopuxa.pdfIn PDF document text
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/13585193825.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/2s771qkii3s957mc079dh0ato4/88850456089.pdfIn PDF document text
    • https://insinkerator.us/images/uploaded/file/28229790577.pdfIn PDF document text
    • http://fresh-j.info/images/uploadedimages/file/deruresagoseragipipo.pdfIn PDF document text
    • http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/92855685961.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/69702429965.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/76853234898.pdfIn PDF document text
    • http://studiostocchi.eu/userfiles/files/kijed.pdfIn PDF document text
    • http://radtel-sport.pl/userfiles/file/vepipegotubifevixuvama.pdfIn PDF document text
    • http://eurosolar.cz/res/file/75233874208.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/folavizulajenejugezugofa.pdfIn PDF document text
    • http://supermarketdv.ru/files/file/dinuwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=mi+box+4k+cast+not+workingPDF 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_off0000bdb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5CD 10716 bytes
SHA-256: 87f734021e92dcadb2d7f949789b8bd2bb59ef1179c31c194b09d9f2922a99dc
font_02_sfnt_off0000eeb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB5 18732 bytes
SHA-256: 2a94a7f452a27e2ce895fdfa9582d1c26649d3aba567d2f856c99d82e0cd800e