Malicious PDF — malware analysis report

Static analysis result for SHA-256 309ef15d2ce526ba…

MALICIOUS

PDF

83.5 KB Created: 2021-06-15 16:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: cbb1f0e373d9aa0bbd53ab8ce780d19d SHA-1: 4ebe99b74c8515fc8fbcb6efc52789bf454c18ac SHA-256: 309ef15d2ce526ba489e468c359a0774b82aedaf343638f873775c28821e9b80
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF contains multiple links to external websites, many of which appear to be compromised WordPress installations hosting PDF files. The document body, though heavily obfuscated, likely contains lures to trick the user into enabling content or clicking a download button, which is a common tactic for delivering malicious payloads. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 8

  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://medvor.ru/uplcv?utm_term=family+feud+board+template PDF link annotation
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b3ef8984db4---fotovifiriputidobowo.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16071fd345e0ce---53027269466.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b477b2ba7cd---pufenituv.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/b1ga5jhiu7uosn45qtc01knah1/34781979003.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/15b9ab9c22f74712ff809b14d778c0ab/dodijudejesadawera.pdfIn PDF document text
    • http://allasclub.com/campannas/file/20999087002.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/01f61988fe1ccf45a0161230fe30eb88/zetararijonobubofome.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c7276e7e0---31805144140.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2a16e5942---lowap.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/5382964df5fce518dea5080a7d456564/xusugomawuwobojizivewafe.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608273b2aa024---jigixurorirekifidunakager.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/1a0404f21c0e4ea7f4274dfd41e3cef6/94861327342.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/a983be68317db510c3f1ab1eb4a11570/93431053503.pdfIn PDF document text
    • https://unosms.us/userfiles/file/48153288509.pdfIn PDF document text
    • http://kids-ex.com/3026400229.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/cb60d7a57f597ff234e3e08020d03540/8866105028.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/6853405586.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd267e15012---bafafidu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000f2ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2AD 5204 bytes
SHA-256: e469a8c3d04c81d641ad51a919226f0bdab13ee67fc1032494a5d7176ae87223
font_01_sfnt_off00010454.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10454 11648 bytes
SHA-256: 4e27db9476c618cab0aaa08d1765bc26b6b1ac3c3f7ca67e7274078ebcc597f5
font_02_sfnt_off00012b73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B73 16204 bytes
SHA-256: c988415812f594187b0a0ed75dc52802e798e1695b49bd300f8412a65040a449