Malicious PDF — malware analysis report

Static analysis result for SHA-256 89c75163e4d0d8eb…

MALICIOUS

PDF

71.0 KB Created: 2021-10-02 23:32:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3a38aafb838fe6be8299988783a14676 SHA-1: 6b21074406e053bba5da9db2661d0ad918a31ee7 SHA-256: 89c75163e4d0d8eb46a6affc1f7dc7a2d1ac65a0a20f5852161adff52aef3ef9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution campaign. The PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://inwebjor.ru/uplcv?utm_term=simple+cash+book+questions+and+answers PDF link annotation
    • http://e-sportis.com/images/upload/54810699861.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/bujak.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/70476732762.pdfIn PDF document text
    • https://gtselect.fr/ckfinder/userfiles/files/wudosiji.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/i196e76fpua1lc8bovvlqkkb73/gexuxul.pdfIn PDF document text
    • http://energy-labels.nl/userfiles/file/37240932513.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/88904882976.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/18029719984.pdfIn PDF document text
    • http://www.benyowsky.com/resources/files/9123659443.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/ho16c371i4opek1732st27o7v7/57463194204.pdfIn PDF document text
    • https://zenit-npk.ru/files/file/9447763329.pdfIn PDF document text
    • https://coastalstudio.com/images/main/file/koroduwejikozes.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/99170698041.pdfIn PDF document text
    • http://snuhonors.com/userfiles/file/purafugelato.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/83959638905.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/76651696207.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/90595419371.pdfIn PDF document text
    • http://freestyler.cz/img/file/kaxazumesaturo.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/wowaripabasatokibufu.pdfIn PDF document text
    • http://dichvubaove.online/upload/files/31716159436.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/73603779180.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/8803807906.pdfIn PDF document text
    • http://euphoriaclub.fun4two.pl/uploads/assets/file/4193427726.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_off0000b222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB222 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA34 16236 bytes
SHA-256: fc270e179c7bc3d2b3b1efe3d13f2d881df8a7a91bb206c574caa22250125596
font_02_sfnt_off0000f3d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D9 11420 bytes
SHA-256: baaba7a94a46df07e4b0f23d77861f56789d306708845c1d259323e30eb6992a