Malicious PDF — malware analysis report

Static analysis result for SHA-256 15c8a5b94863b9a4…

MALICIOUS

PDF

80.2 KB Created: 2021-09-15 12:38:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 14f0788941ef3fc13bffcc20e20d6e79 SHA-1: dd3a7e3585362fc4a04b25f43531867e6fbbfbef SHA-256: 15c8a5b94863b9a43a7b86ecc423b54d69877796687dd0dafa26d1cc256f6ac0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which are configured as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high likelihood of these URLs being used to redirect users to malicious content or phishing sites. While no scripts were explicitly extracted, the nature of the embedded URLs and the link farm heuristic suggest an intent to drive traffic to potentially harmful destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://ketchas.ru/uplcv?utm_term=ar+market+apk PDF link annotation
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0b2a2d5b3---vixoxu.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/kevafobotegokiwizidumarum.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/68103543407.pdfIn PDF document text
    • http://seattleteriyaki3.com/uploads/files/vizowesidafaxaja.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12730457360.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/77991165854.pdfIn PDF document text
    • http://egitara.com/upfiles/files/31262165369.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210909021946.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413be2a0280---wegoxux.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/46707586866.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/86286310664.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210912041616.pdfIn PDF document text
    • https://nocnepal.org.np/ckfinder/userfiles/files/votegevazofu.pdfIn PDF document text
    • http://studioguatta.it/userfiles/files/69245753969.pdfIn PDF document text
    • http://zawodydrwali.pl/app/webroot/userfiles/file/82751647987.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/sotulik.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/31449573650.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/gewuguxetifirutelisuva.pdfIn PDF document text
    • https://lapakunited.com/contents/files/vakukoruzodoja.pdfIn PDF document text
    • https://www.bnbtravels.com/ckfinder/userfiles/files/28827621106.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/gavularinuxava.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/80934757707.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/fitoriredudugixa.pdfIn PDF document text
    • http://linkipt.com/_UploadEditor/files/89745526299.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/nebuluzaxafiv.pdfIn PDF document text
    • http://energyexcess.com/userfiles/file/56181486971.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_off0000d6b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B8 18156 bytes
SHA-256: 79955699dd51a7d03ad8857b386df8d640bf69a94cae61526250f3f9bcfb9523
font_01_sfnt_off000104f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F5 9956 bytes
SHA-256: 0a24216fee9225e1919ce3c58f9d010af80b2ddf54e0cb8ada629c7887fe4f3e
font_02_sfnt_off00011b0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B0A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1