Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc1bfcc285c1c0cd…

MALICIOUS

PDF

81.0 KB Created: 2021-09-20 00:02:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 46003e2df1b0fa1b31052021eb053bcb SHA-1: f89b8a1901fdec8414b8bb35a197f3da471f017c SHA-256: bc1bfcc285c1c0cd61083d85407ffdb120b224f7f6e72820369c86dc63540d01
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs, many of which are hosted on disposable domains. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a deliberate attempt to create a link farm, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or delivering a secondary payload via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://laborke.ru/uplcv?utm_term=video+player+with+subtitle+apk PDF link annotation
    • http://tonioloclaudio.it/userfiles/files/pafetabo.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/70455590193.pdfIn PDF document text
    • https://geneolock.com/ckfinder/userfiles/files/rekepibu.pdfIn PDF document text
    • https://qualitygums.com/userfiles/file/21967072197.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/18630123048.pdfIn PDF document text
    • http://ativn.com/upload/file/26560190192.pdfIn PDF document text
    • http://condosworld.com/abisol1/userfiles/files/83582677214.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/78365363178.pdfIn PDF document text
    • http://oppedisanorobertosrl.com/userfiles/files/44364109176.pdfIn PDF document text
    • http://hydrem.ru/images/file/93639598134.pdfIn PDF document text
    • https://sukhayurveda.in/userfiles/file/jalapomezegipuz.pdfIn PDF document text
    • https://tranthachcaodanang.com/uploads/image/files/bajuru.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/5882945290.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/sedisifowi.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/6792579334.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/latalugibow.pdfIn PDF document text
    • http://www.sm.ac.th/ckfinder/userfiles/files/pirorutamamugebatonolug.pdfIn PDF document text
    • https://nadrozmerne-sklo.cz/uploads/75659350947.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/66749944578.pdfIn PDF document text
    • http://autothudo.vn/upload/fck/file/ridamos.pdfIn PDF document text
    • https://susta.vn/userfiles/file/2143229260.pdfIn PDF document text
    • http://quimis.net/js/ckfinder/userfiles/files/73248894562.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f05058216d---64964354685.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/tizapijifejakido.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_off0000d500.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD500 18652 bytes
SHA-256: f6c19349878836c645501f44694025bba5bc76f600d659292a20385312f5adfd
font_01_sfnt_off00010547.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10547 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5E 10884 bytes
SHA-256: 0519093cbeefbdba8ffec28ae0c7d039b27a4ca73806f069489df12777d78193