Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f1663e4fd491ad2…

MALICIOUS

PDF

84.4 KB Created: 2021-09-15 18:01:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ddaa766064beed8c0017b90856f3c646 SHA-1: 15138c82fa1621f2539a0e5bd878b0ae9a1db098 SHA-256: 4f1663e4fd491ad21e4955f997f2e65b40eaadcc69f34f376f5f87f49ff2d430
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary attack vector appears to be luring users to external sites via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://ketchas.ru/uplcv?utm_term=gta+five+cheats+pc PDF link annotation
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e90e29040a---nenuwaniwijinezenilipo.pdfIn PDF document text
    • http://www.sas.edu.mn/ckfinder/userfiles/files/34197946039.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e91033a1f0---xenebemavubevejalem.pdfIn PDF document text
    • http://patrickstaxi.fr/userfiles/file/80112456156.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/57615429785.pdfIn PDF document text
    • https://medarbindia.org/ckfinder/userfiles/files/dabexunavuwibu.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/bufofekajed.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613f382ec8a34---34926514045.pdfIn PDF document text
    • http://dorisemitchell.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/73446227583.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/48103709189.pdfIn PDF document text
    • https://vokalensemble-vocembalo.ch/userfiles/file/1416120743.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/vezejapodowonananor.pdfIn PDF document text
    • https://qualitygums.com/userfiles/file/lalatadusejamosuwagig.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/a59a210a0f866e6d559ff198b05ba24d/53894216072.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/kararukim.pdfIn PDF document text
    • http://gustosandvic.com/ckfinder/userfiles/files/42617368335.pdfIn PDF document text
    • https://promtour-rural.ro/userfiles/file/wiwojisewup.pdfIn PDF document text
    • http://maslatalaia.com/userfiles/file/17872077734.pdfIn PDF document text
    • http://tinhdaurosa.com/Images_upload/files/50747613071.pdfIn PDF document text
    • https://speak82.com/_UploadFile/Images/file/xubuzir.pdfIn PDF document text
    • http://dolekkoyum.com/admin/UserFiles/file/nozugonidenidimori.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/pakewepupezekemi.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_off0000e593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE593 18540 bytes
SHA-256: 947e1eb988af77553a1c11146eb1d92fdf3697593e275e89fba05eaf76878305
font_01_sfnt_off00011526.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11526 10312 bytes
SHA-256: 41f5852a41c3a344bfa71d2d8a657735d8839c4bde4f1504c1108b56e179d45c
font_02_sfnt_off00012c9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1