Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1f6b2f1851d5cc4…

MALICIOUS

PDF

73.8 KB Created: 2021-09-09 02:46:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3c2590a0f4bf5576e95cda7205cddc07 SHA-1: 21563ed272569805e4ef31399f692ab69f9a73cd SHA-256: d1f6b2f1851d5cc49469b41cfa829eed3581ade6d8ca72edf658ab37fdf25e1e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a link farm detection and a high ML score, indicating malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to redirect users to malicious content, likely via embedded JavaScript.

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 https://www.sibirprokat.ru/ckfinder/userfiles/files/93885061875.pdf In PDF document text
    • http://nguyenhungstone.com/uploads/image/files/88568062966.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/3107311936.pdfIn PDF document text
    • http://hsi-international.com/ckfinder/userfiles/files/81291312686.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/6028362196.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/95716300892.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/501816d614ced7d3c7bb98784a6978d4/30338848562.pdfIn PDF document text
    • http://pevak.info/UserFiles/File/bipifebajolevomisamexod.pdfIn PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/nijoruwopuwo.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/54621367793.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/turilosajununureteku.pdfIn PDF document text
    • http://munnartourism.com/uploads/file/vesesujofakeratirunifag.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/um8tk58pfqj4973ig85hi6o6e9/fuxurakiruposeporux.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/ropupifixowef.pdfIn PDF document text
    • https://basundharamart.com/userfiles/file/jelositenuboxudonoz.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/gugonuwibosutisasasojoval.pdfIn PDF document text
    • https://srinivasagroup.com/ci/userfiles/files/fobulorop.pdfIn PDF document text
    • http://gizmakina.com/depo/sayfaresim/file/gugiziwusalasumarobodo.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/63002565121.pdfIn PDF document text
    • https://warungmimpishio2.com/contents/files/womenini.pdfIn PDF document text
    • http://faurerom.com/userfiles/file/zojet.pdfIn PDF document text
    • http://belniig.by/public/file/26377405377.pdfIn PDF document text
    • http://homelife-superstars.com/image/files/nomuliferaxoxem.pdfIn PDF document text
    • http://hrudolf.com/userfiles/febew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=tv+all+channel+apkPDF 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_off0000c0bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CD 16512 bytes
SHA-256: 6dd75048edd87c5e910060c9f00bfbd5273685b2cb890e18f7f34f4fb2437fbf
font_02_sfnt_off00010349.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10349 10016 bytes
SHA-256: c91af0c8cccda2b451a4f2e69a8adca95a3b93969e77982018b73cda33c127a9