Malicious PDF — malware analysis report

Static analysis result for SHA-256 88b9ce8e005b0fad…

MALICIOUS

PDF

68.2 KB Created: 2021-09-26 14:08:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 9b41977e7fa468260043584c34da79fa SHA-1: 3df8f8e5726563124d5cb8fc2600450bd01604cb SHA-256: 88b9ce8e005b0fad48f0567133f9a58645e639fca1b15f0ad1e5ba148971c7c0
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains embedded JavaScript and a large number of external URIs, many of which point to disposable domains and appear to be part of a link farm. The embedded JavaScript likely attempts to redirect the user or download additional malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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 http://annabarons.lv/files/files/34570541608.pdf In PDF document text
    • http://harlit.com/ckfinder/userfiles/files/20210917_121820.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/53908967795.pdfIn PDF document text
    • http://myesen.life/userfiles/file/mijedepuranubetepa.pdfIn PDF document text
    • https://ilonew.tasksplan.com/userfiles/files/15157191407.pdfIn PDF document text
    • https://educationindiajournal.org/ckfinder/userfiles/files/7693634262.pdfIn PDF document text
    • https://dogathermalhotel.com/resimler/files/gerugo.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/66200642818.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5bba18a85---5793593840.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/dejumunumaxuzigus.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/6hups4dfv0fhuhigqpkflnhk29/kidajodajabidogomeve.pdfIn PDF document text
    • http://www.mmalappeenranta.com/tiedostot/files/44311028937.pdfIn PDF document text
    • https://sistemagestiondpr.com/userfiles/file/86606051025.pdfIn PDF document text
    • http://grandfiltr.com/files/file/dorimularubevopuvininat.pdfIn PDF document text
    • http://chiesamadremarsala.eu/userfiles/files/pilolatiwibabewiligibu.pdfIn PDF document text
    • http://vrieshorst.nl/images/uploads/file/kipaxubov.pdfIn PDF document text
    • http://surmounttravel.com/userfiles/files/19093697001.pdfIn PDF document text
    • https://lawtutors.co.uk/js/ckfinder/userfiles/files/sexano.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/59026798639.pdfIn PDF document text
    • http://amicissiapiemonteisa.it/userfiles/files/42524278494.pdfIn PDF document text
    • http://poongdung.com/FileData/ckfinder/files/20210924_56E88D1A1B9779A4.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/wupigumosidapunaje.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/17136688268.pdfIn PDF document text
    • http://franceplus.fr/userfiles/file/24952465848.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+unhide+hidden+files+in+androidPDF link annotation
    • 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_off0000af64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c77b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC77B 10628 bytes
SHA-256: 9f1880245c32fedf1a5e313d13d64d9b187457bc1a81c9694fdb91980830b5be
font_02_sfnt_off0000dfba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBA 14216 bytes
SHA-256: ed6be88043c84f3053212ebf018eedcc937bea70edaacb1a2c465ae49ba270f9