Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f6d10d3b1db2d43…

MALICIOUS

PDF

86.7 KB Created: 2021-08-30 04:15:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 36b61e10508f57b6646de17504882207 SHA-1: 91cc995581edb200484c84ec6d6855e01254218e SHA-256: 8f6d10d3b1db2d436b4350eb503ec4fe8f2f3f2da76f23fcf2726f8f4d45c2e7
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised WordPress sites, suggesting an attempt to redirect users to malicious content or downloads. The presence of multiple links on disposable hosting further supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d5756a776---fusubaxasoso.pdf
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/33ac309730d7db7e20f607e1c8bc061a/5418216201.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094083c10099---gowofiwaroboboxegeziwak.pdf
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/09f181a8800dfdc92f153d1737ed2022/58574307516.pdf
    • http://yuanjen.com/ckfinder/userfiles/files/mijuxudonowot.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/2tv7tfnmelr661mef0t46e8cd2/81522679112.pdf
    • http://horizonpestservices.com/userfile/53342467362.pdf
    • http://shs1977reunion.com/clients/41590/File/46538441522.pdf
    • https://pjkconstruction.ca/images/file/fikugeboket.pdf
    • http://prograsifkalip.com/files/35075171457.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/a3f51oaahcncmaggjed9imjk26/zuxogifiwidamuladesigoxi.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/2945ccdef47dcb2fdc3aa1d81d428955/polad.pdf
    • http://forma8.kz/ckfinder/userfiles/files/linufudazev.pdf
    • http://sacoorhealth.pt/site/upload/file/75747094742.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/d8013eeac0bf9d7a45044c907227b74c/fezepamugobedidipas.pdf
    • http://bukharaatlanta.com/sites/default/files/file/93489449484.pdf
    • http://slp70.com/clients/873855/File/16474108460.pdf
    • https://rieker-consulting.eu/files/file/76183506503.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf9bb9a7f1---2385205392.pdf
    • http://smenergy.kr/uploaded/file/39226390560fb48654a478.pdf
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160917e3b6610f---wexef.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/94a255770cf1fa5b6d5a913c7f987c59/xojakuseluzilumunugulijom.pdf
    • https://derey.nl/app/webroot/files/userfiles/files/sigitodanemixetomo.pdf
    • http://robertfeinberglaw.com/images/edit_images/file/48308320883.pdf
    • http://sbox-technology.com/upload/datoteke/xewozamikesesita.pdf
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/b3865d56177a95bdf8e419a65c373da5/gojazixaxikijukejik.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=twilight+of+the+elves
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/7088c144169f97cb677605376f66112a/lisabokegefatimobaradesof.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed00.bin
b0fa93cf0fbfae685b57c3fdd1f105670134281acc07e67f80d9d1bbd87b0c43
pdf-font-stream PDF embedded font (sfnt) at offset 0xED00 10244 bytes
font_01_sfnt_off00010436.bin
9058467897c68f76fb61527f49645b9fccac27b5245eadaf8e288e4f8aed12f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10436 18992 bytes
font_02_sfnt_off00013550.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13550 16792 bytes