Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a91f30f6677059c…

MALICIOUS

PDF

88.3 KB Created: 2021-09-18 01:03:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 10601d9cd46967d770cf136cbeb73d09 SHA-1: eef541c873313d5c88fb3f1162d0d688a4e3779a SHA-256: 8a91f30f6677059c48f423c3245ea4019c5af6cb43df4b74ca318d586365b58a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous embedded URLs, many pointing to unknown or potentially malicious domains, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used as a lure to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://bimore.vn/webroot/img/files/94486550139.pdf In PDF document text
    • http://tuhocxuatnhapkhau.com/uploads/ckfinder/files/95048054986.pdfIn PDF document text
    • http://thomas-zigon.de/images/file/4741168654.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/pavunubofoniladuwujozaz.pdfIn PDF document text
    • https://lederstuehle-shop.de/ckfinder/userfiles/files/pimububejisobavoraguzunun.pdfIn PDF document text
    • http://stmrcstvm.com/userfiles/file/27478014027.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/19809336983.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/nurimalarinizibafotedi.pdfIn PDF document text
    • http://marchmont.ru/imgs/file/tuzojerotililaluve.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/burewuxedibixin.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210910185532.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/kugavetusudijodokosezuju.pdfIn PDF document text
    • http://autowassenindex.nl/images/uploads/79395236066.pdfIn PDF document text
    • https://krantiservice.com/ckfinder/userfiles/files/jaderabo.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/44247aeb21ba919a26f6814f1180fd92/wiwewejanel.pdfIn PDF document text
    • https://www.traitagri-solutions-alternatives.fr/ckfinder/userfiles/files/karowikikezetokudunaxifef.pdfIn PDF document text
    • https://homestayhoian.thamtuddt.com/uploads/image/files/fixutikonepirefudiliwizi.pdfIn PDF document text
    • http://riccaassociati.eu/userfiles/files/bakipigudilawedojugevamuv.pdfIn PDF document text
    • http://client.diffuse.info/files/kenorudobuko.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/vogobasewureviposus.pdfIn PDF document text
    • http://condominiobrisasdelnorte.com/userfiles/file/2164433011.pdfIn PDF document text
    • http://dungcumaymoc.com/Images_upload/files/96131129412.pdfIn PDF document text
    • https://candica.pl/ckfinder/userfiles/files/80397719417.pdfIn PDF document text
    • https://areicon.com/images/file/wofufuradosubinojuxe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=ogilvy+on+advertising+pdfPDF 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_off0000f113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF113 18728 bytes
SHA-256: 61429185ea76dad9070dbea89b7daf4a45b64e60c5e4f044569908ead25e9111
font_01_sfnt_off00012237.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12237 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013a4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A4E 10880 bytes
SHA-256: 7a857ceb349b8ea49efb3230f9e33db42ea781cb3dee6115390ef5e2e839095a