Malicious PDF — malware analysis report

Static analysis result for SHA-256 8336c556e6fbe601…

MALICIOUS

PDF

73.9 KB Created: 2021-09-20 07:20:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 85d327894192b4687929fd9c15838959 SHA-1: a1b1102b57954348acb2d349df45fd1de527ecb7 SHA-256: 8336c556e6fbe6017059a21e9faba8ddea0be1f7d1e6e3d1e905764201f199a5
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable domains and structured as a link farm, indicating a distribution or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via the linked PDFs. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://archism.ru/uplcv?utm_term=padmaavat+full+movie+online+free PDF link annotation
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/3682213008.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/111037402292.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/30912305675.pdfIn PDF document text
    • http://baove24h.org/upload/files/turikonofanujefevumik.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/mubadafamutawu.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140affc11df0---88077163196.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/33951554184.pdfIn PDF document text
    • https://candica.pl/ckfinder/userfiles/files/96300412632.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109101047487835.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/sepekidunetilokazo.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/rilex.pdfIn PDF document text
    • http://world-green-hope.com/uploads/files/wanawinobigavepu.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/tomotilemedemavamalor.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/jeboxetuxivigawejenovo.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/momukavopizatofogif.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/49585348800.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161426fcb92885---bixikeketudanikedapunita.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/69290491399.pdfIn PDF document text
    • https://discovercefalu.it/_data/images/file/vejogirovupu.pdfIn PDF document text
    • http://yildizteknikelektrik.net/resimler/files/88312958499.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/8186367616.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/dufigukesazogolopagi.pdfIn PDF document text
    • http://vssteel1999.com/ckeditor/userfiles/files/desovapufijif.pdfIn PDF document text
    • http://kalikraft.com/images/file/sukuluvubawavavepurogi.pdfIn PDF document text
    • http://iphysiology.ru/upload/91531880324.pdfIn PDF document text
    • 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_off0000bcd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCD6 10516 bytes
SHA-256: 490111e8763f0ee412470575014389701678a3cd765daa2583e9b187ac4625f3
font_01_sfnt_off0000d4b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B7 17336 bytes
SHA-256: 8b75b47af97f02647f19f0b904dde1dfce02cdeaee1efd1dba48143b8f545648
font_02_sfnt_off00010175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10175 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1