Malicious PDF — malware analysis report

Static analysis result for SHA-256 97b8699b08fddb94…

MALICIOUS

PDF

92.0 KB Created: 2021-09-24 11:34:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 02e4139df8e9860d9bbf155511e5e786 SHA-1: 64008add2f1604c105a9e843e9388f0416b2c9e1 SHA-256: 97b8699b08fddb9478170397f9fbf5f2dd655a3ad33f0078fe0b7b205e33e7ab
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Heuristics indicate the document functions as a link farm, pointing to multiple external URLs, some hosted on compromised CMS platforms. The embedded URLs and the nature of the heuristics suggest an attempt to direct users to malicious or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://salman-group.com/userfiles/file/84545419546.pdf In PDF document text
    • https://sieuthimaytinhcu.vn/upload/files/96104429661.pdfIn PDF document text
    • https://ssekolkata.com/ckfinder/userfiles/files/83003663842.pdfIn PDF document text
    • http://el-system.jp/uploads/2012/files/guzalegi.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d877d9933b---kejuludip.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/kativoko.pdfIn PDF document text
    • http://yourmoneyyourbank.com/uploads/File/63934322001.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/24721504833.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161430ca19a21d---91365244908.pdfIn PDF document text
    • http://stellarp.com/userfiles/file/tisubuzujerajenawopaka.pdfIn PDF document text
    • http://nuocmambason.com/upload/fckimagesfile/8c48ebebf9e8a08ca708c1d014053ff8.pdfIn PDF document text
    • https://autotronics.vn/userfiles/file/xaxik.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141636258635---zilirag.pdfIn PDF document text
    • http://nhadatv.com/webroot/img/files/fonud.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/wakibomexoxim.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/254c1e575032ec326b9c4e66c2c61725/romuxugejubosuwinizipidad.pdfIn PDF document text
    • https://texasbordervolunteers.org/userfiles/file/57303480822.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/92316590807.pdfIn PDF document text
    • http://olympicburger1988.com/uploads/files/pevuv.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/10963293299.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/zurezatisexov.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/5942640013.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=snow+bros+hack+apkPDF 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_off0000f886.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF886 22760 bytes
SHA-256: a995379103c04d7fac8b5ef7c7145b1bbd76bd16262a560b5bae1d1eeb43d538
font_01_sfnt_off00013351.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13351 10496 bytes
SHA-256: 11da959652802ef8527b9e10fc7f57645ff8027cdcc2f6773a0956c67013627b
font_02_sfnt_off00014af8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1