Malicious PDF — malware analysis report

Static analysis result for SHA-256 79830e959de6fbab…

MALICIOUS

PDF

94.9 KB Created: 2021-09-22 23:59:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c889fedad25e8c70e7485678471ba272 SHA-1: b16b13914bb6e843a000d4718bbaa33ca38d43c8 SHA-256: 79830e959de6fbabe76f17e6cf84ee030a59195706337ee61274ed17e0d0f6e0
196 Risk Score

Malware Insights

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

This PDF document was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. The presence of a 'Browser extension / update installation lure' heuristic indicates the document's content likely prompts the user to install malicious software. The numerous external URLs, many hosted on compromised CMS platforms, suggest a link farm designed to redirect users to malicious sites. No scripts were extracted, but the overall structure and heuristics point to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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 https://nomylo.ru/uplcv?utm_term=newest+android+os PDF link annotation
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16146cac5deeac---3436707476.pdfIn PDF document text
    • https://nayyaralidada.net/alpha/ckfinder/userfiles/files/xatatop.pdfIn PDF document text
    • http://reginahajo.hu/_user/file/59115341142.pdfIn PDF document text
    • http://mfahk.com/upload/files/45685704213.pdfIn PDF document text
    • https://ourguarantees.com/userfiles/file/20349132292.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/25818423234.pdfIn PDF document text
    • http://louisamerino.com/userfiles/file/webuwojuz.pdfIn PDF document text
    • http://racecross.com/upload/edito_fckeditor/file/lunir.pdfIn PDF document text
    • http://hophungvietnam.com/app/webroot/uploads/files/jugipeleriwugigabi.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139dad429378---dikan.pdfIn PDF document text
    • http://kzlo.pl/fotki/fotki/file/92952387254.pdfIn PDF document text
    • https://cokhivietuc.com/img-vietuc/files/zikuwokojesej.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e72f2f2833---43270429940.pdfIn PDF document text
    • https://budapestpainter.hu/ckfinder/userfiles/files/diketakavunoj.pdfIn PDF document text
    • http://hyundai-dongdo.vn/images/files/wenotanejedewexogodago.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/d1bfd52e33afc56a5443b0be4a565e03/zepagetadaregijodava.pdfIn PDF document text
    • http://yurisolomko.com/userfiles/file/lakev.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/34779213945.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/fezuzaxaliwos.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/7aa2bdb150744455c35d4cbf7cd4e249/79969099988.pdfIn PDF document text
    • http://hanahana.vn/media/ftp/file/wupekon.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_off0001107d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1107D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012894.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12894 10256 bytes
SHA-256: 8edb8e52a9aef32a3d1361e2b2de936ae54f0f5d4b9861e8b1f755e6594c62f1
font_02_sfnt_off00013fd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FD4 17928 bytes
SHA-256: ecc11a79f34d7befe1c49fb2260c42a1371664cc9172188935020199391f3e9a

Open this report in the interactive analyzer, or submit your own file for analysis.