Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc86855a524aaf5c…

MALICIOUS

PDF

90.2 KB Created: 2021-09-15 09:42:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9763e3a4a5aa0b4b848b35d742d7b86e SHA-1: 2dc7142c0d54d08492119f191efdd0a08f74672c SHA-256: cc86855a524aaf5c94e9722aee73f44bf0aeeb1e483648a5d6b209a75e45f282
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to PDFs hosted on disposable domains, indicating a link farm designed to obscure the ultimate destination. The presence of external URIs and the link farm heuristic suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/6eb22c8ea94e01137d3aa3efd02e7db8/zofixisemi.pdf In PDF document text
    • http://innotack.com/userfiles/file/siluzexejegivoterewodesi.pdfIn PDF document text
    • http://linker-apps.com/files/ruxojojiluxowabukidan.pdfIn PDF document text
    • https://digiconelectronics.com/media/13185989323.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109100005571309.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16139cb6c9ac1a---55670069694.pdfIn PDF document text
    • https://ottopianos.nl/files/90658591155.pdfIn PDF document text
    • https://schachverein-marchhoefe.ch/fcsr/news/upload/file/wanekufovokavutod.pdfIn PDF document text
    • http://sasnowosielski.com/ckfinder/userfiles/files/94748144544.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/dogeburuzufiji.pdfIn PDF document text
    • https://banktapeunadana.com/tapeunadana/bank2/admin/userfiles/file/82219055607.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/duzizozedewugejoda.pdfIn PDF document text
    • https://akvanova.ru/sites/default/files/kogigak.pdfIn PDF document text
    • http://riviera.az/userfiles/file/befupatedenikalisujetabi.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/99455516204.pdfIn PDF document text
    • http://trovas.com/userimages/49309255481.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/noxasujuxozopudosuzebib.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/bobawaxum.pdfIn PDF document text
    • http://tc-muehlacker.de/data/tcmuehlacker/userfiles/file/52415656047.pdfIn PDF document text
    • http://violetstudio.in/userfiles/file/5255732420.pdfIn PDF document text
    • https://signatureshreyas.in/userfiles/file/97988676256.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/zinuvinorerirovalofe.pdfIn PDF document text
    • https://superpackeg.com/userfiles/file/temovarujifuvidebafusuba.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/17182574133.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/rolalozusew.pdfIn PDF document text
    • http://mobil-tech.com/files/gabatiwifobawazelo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=nice+words+that+start+with+the+letter+yPDF 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_off0000fa2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11244 10540 bytes
SHA-256: 15d6e901ec92215cfe407a5db1f9d68ce73c5d064844f49599ee9e98b876fe18
font_02_sfnt_off00012a85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A85 18712 bytes
SHA-256: fbfcc6c8b06a664aed2f3b71d0e96530e26f6737823f12294cb592d29d1474dc