Malicious PDF — malware analysis report

Static analysis result for SHA-256 4720c31d25425bb5…

MALICIOUS

PDF

73.3 KB Created: 2021-09-19 01:01:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1d96f3afa5affc1e4570ff223c26c1c6 SHA-1: 154fe48a8c7892e2195b6faeaafabd9ec9d4196b SHA-256: 4720c31d25425bb5e79debe81413fc373bfa6a46b8a28dc79301b838e2161b1c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript which is flagged as malicious by ML classifiers and ClamAV. This script likely redirects the user to external URLs, such as the identified `https://medvor.ru/uplcv?utm_term=download+game+lucky+patcher+tanpa+root`, which is a common tactic for phishing or downloading further malicious content. The PDF also acts as a link farm, hosting numerous other PDF files on disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://medvor.ru/uplcv?utm_term=download+game+lucky+patcher+tanpa+root PDF link annotation
    • https://lanjutpt1.com/contents/files/24245095611.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/sojetowubipogafaxapiwored.pdfIn PDF document text
    • https://florerialafloresta.com/ckfinder/userfiles/files/81899031732.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/54224071007.pdfIn PDF document text
    • https://xistenze.nagydavid.com/files/files/75251849610.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/30874210691.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/tuzimelevisawisopipin.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/fojozimitevaxitom.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/ramujadunapigugen.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/1840178272.pdfIn PDF document text
    • https://landbar.com/app/webroot/js/ckfinder/core/connector/upload/files/661440539.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161409c8ca4ca7---lorijuzoxodanu.pdfIn PDF document text
    • https://toscanafantastica.com/userfiles/file/5943971833.pdfIn PDF document text
    • http://rund.cz/UserFiles/File/povasejopexum.pdfIn PDF document text
    • https://hondaotohaiphong.vn/upload/files/fesakurinifufuzetagim.pdfIn PDF document text
    • http://www.fishandcosolicitors.com/uploads/files/wurutuxemezeros.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/gitorulukagasefusupidid.pdfIn PDF document text
    • http://exima.kr/userData/board/file/51486480990.pdfIn PDF document text
    • http://fashionflutters.com/ckfinder/userfiles/files/95390753708.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613492d966c5e---bikifefivatibonutamuro.pdfIn PDF document text
    • http://baharev76.ru/userfiles/file/biranenu.pdfIn PDF document text
    • https://art4you.sk/editor_uploads/system/files/69606438330.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/vigufa.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/51195291573.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_off0000ba2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d241.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD241 16428 bytes
SHA-256: 46795fa2547f400781bca73ef234d6d6ad2a00f455ca3c2cfffccc0133b9a94d
font_02_sfnt_off0000fc76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC76 11096 bytes
SHA-256: 36ad46f259fafcb3c9348a0eebacda09cad2ba15c4d16e94c72d19663f8d19ff