Malicious PDF — malware analysis report

Static analysis result for SHA-256 63213161e4abcb4d…

MALICIOUS

PDF

71.8 KB Created: 2021-09-10 05:32:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1061c11d68aabae1f49140f54345f2a6 SHA-1: 5eb705e07be3db46498849abe24d4383178291a4 SHA-256: 63213161e4abcb4d74cf837099f76d30fd01dd8942c46253c5fb8b9d55b3a9e2
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting and appear to be part of a link farm. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high likelihood of this document being used for phishing or distributing further malware by directing users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://catamma.ru/uplcv?utm_term=publicidad+kleppner+pdf PDF link annotation
    • https://sindonis.com/userfiles/file/bufatesit.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/62337615127.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/53786597671.pdfIn PDF document text
    • http://ekbdrive.ru/ckfinder/userfiles/files/73819654550.pdfIn PDF document text
    • http://elektromig.pl/userfiles/file/12275984479.pdfIn PDF document text
    • http://abwessex.com/uploads/files/wovenanasuzegujutidawol.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/9820268150.pdfIn PDF document text
    • https://tarsiman.ee/files/file/gebudajozilu.pdfIn PDF document text
    • http://3e-machinery.ru/app/webroot/filesfiles/pugamusafatidaza.pdfIn PDF document text
    • https://reaga.net/js/ckfinder/userfiles/files/penurapemuxadumosuxez.pdfIn PDF document text
    • http://kbchina.de/upload/46965526608.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/11503237788.pdfIn PDF document text
    • http://sinice-rasy.cz/files/file/mibofuzituluravofuxe.pdfIn PDF document text
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0903/889f3d21c9be1fb649ba118c425015dc.pdfIn PDF document text
    • http://saga.diamonds/uploads/ckfinder/files/pujukufiwe.pdfIn PDF document text
    • http://applexin.com/ttpsea/files/file/zapanepivuwizola.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/lawexutikes.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a327c10f44---70761197628.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/fijubisunonumolimig.pdfIn PDF document text
    • https://edouardweil.com/userfiles/file/83492105885.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/dururudigojedew.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/40056549727.pdfIn PDF document text
    • http://first-group.kr/ckupload/files/49811676962.pdfIn PDF document text
    • http://connect-senior.ch/uploades/userfiles/file/danuwowufu.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/tikufikimabivanirob.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_off0000b5a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5A3 16756 bytes
SHA-256: 2cfcd7102727c2a9a04f092b8db9bd054a3b72e881f358de0d6246dce6dee272
font_01_sfnt_off0000e0aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AA 10560 bytes
SHA-256: 97a9cdb90f9c3cae0bfeb45760672164ef2296d710f45b2e1dcbc373a87bafb3
font_02_sfnt_off0000f891.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF891 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1