Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ac38f6d5e645412…

MALICIOUS

PDF

81.4 KB Created: 2021-07-05 21:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 11d1193a50bc47a3201d493dd066a399 SHA-1: cf82016642c3ba6e45d7ceb519b4919a608756ca SHA-256: 5ac38f6d5e645412ec4cf2aef43780b1dcf2a2058c46cabcb8c6b365ae5257df
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to obscure the final destination. The document body is heavily obfuscated, preventing analysis of its direct content, but the overall structure and heuristic firings strongly indicate a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/md5npn8hcoa5vkio0vk4du1qo0/47579279661.pdf In PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c034e48ad79---donumof.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/68702799704.pdfIn PDF document text
    • https://nestaerospace.com/uploads/file/gurowodekezituzuwunufoze.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/tukubipaf.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/o9h3al1u6j0usgeee9appkoo1q/16609470601.pdfIn PDF document text
    • https://langestrand.se/anvandarbilder/204/files/todifarezaxunulamagoguvi.pdfIn PDF document text
    • https://hotelindigha.com/FCKeditor/file/26426077304.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16088a234acf7b---jijekudenanepoget.pdfIn PDF document text
    • http://grapevinewinerytrail.com/clients/876125/File/83864170990.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3db16c770---70503999024.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/57ca73215179507179b9a34a14f9e9b8/21586304849.pdfIn PDF document text
    • https://glbtrader.com/userfiles/file/wigegavujumakizejosir.pdfIn PDF document text
    • https://advik.net/userfiles/file/55477189774.pdfIn PDF document text
    • http://amblesidewindermere.ca/fckuploads/images/file/80163893993.pdfIn PDF document text
    • http://inwallendorf.de/userfiles/file/8438180768.pdfIn PDF document text
    • http://parvazyab.net/basefile/api203/files/xukibelesixemiduxe.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d850ecde35e---makug.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a0440853f---kewof.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b23e320cf7c---javerasipibemegezawulaka.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/m6fqn4hrk2d42pt0k4l21ti923/vatodilukosuremogapodob.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/bfe74f55d24e96e62a2f1d2772685fd2/53927462634.pdfIn PDF document text
    • http://abaj.cz/UserFiles/File/kibajitanukodivuzaw.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/73253603530.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=plume+and+feathers+sherbornePDF 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_off0000d882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD882 17376 bytes
SHA-256: 513b106a2a35eec3ef6278ba856c0d3025c8327ee3cc842c71cd8c41670fcfd5
font_01_sfnt_off0001061e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1061E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E35 10768 bytes
SHA-256: 60ec0e0dcb58c61e16e1553677bca43df7d29726db1cc581209e38acc91c5328