Malicious PDF — malware analysis report

Static analysis result for SHA-256 87d91997f911652a…

MALICIOUS

PDF

93.2 KB Created: 2021-08-21 00:55:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: b26d8301dfd6c93a4c7c98771716695d SHA-1: 8ff8f1e70fa65983d2c4b7a5f56fd44fd4e32773 SHA-256: 87d91997f911652af1c8a5a951c68edfc31e611112e02fdf2ac78a9fc610abef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/5a1e57826755648b55fd6285b4435a6a/fikikunur.pdf In PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/a3098103c7fbe865b4a360b43f25e3b9/nepavuzikixodaso.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5cbe173ef1---92745761513.pdfIn PDF document text
    • http://modra-skola.cz/userfiles/file/42410827486.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/qoobsivhof050f6q3mmet5pa7o/23604402001.pdfIn PDF document text
    • https://lacecinella.com/writable/public/userfiles/file/zoxipepeges.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/53c9bft32bms1cj14duqe3rq3c/netasobakof.pdfIn PDF document text
    • http://fogathajtohirek.hu/fckfiles/file/bulolorox.pdfIn PDF document text
    • https://idd.no/ckfinder/userfiles/files/98856969028.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a01367f2c8a---13722971031.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/8004e485192b913d8b946a6ff57bf89c/97604528167.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d6f19e32bd8---tixixarekime.pdfIn PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bikowosegozujebana.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bef6e21e834---71021588724.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/9787728212.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/setatarisu.pdfIn PDF document text
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/5268a3a38fbcdec6908e9f2a4f8cde4a/98750437106.pdfIn PDF document text
    • http://vce34.ru/attachments/file/12572977369.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/61ca52ddc15fcb6e02f37c2ebb10e385/jijimewopinanalataled.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611d7fe21489f---zanaravuluguvaro.pdfIn PDF document text
    • http://abhinavabhishad.org/userfiles/file/90389807726.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/81331207206.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=spektrum+dx6+manual+pdfPDF 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_off000102e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102E7 10816 bytes
SHA-256: e505bd8f1b0528dfbd67f328e4b63b456dfa12c6e93e58826cdd8f3d828bec43
font_01_sfnt_off00011beb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BEB 19136 bytes
SHA-256: 2dc4d64edbbb72d7dc60ce7b552c577065bf22736ae818ef9c482fd59b7883e0
font_02_sfnt_off00014ef8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1