Malicious PDF — malware analysis report

Static analysis result for SHA-256 281ad5931869bc33…

MALICIOUS

PDF

85.5 KB Created: 2021-07-17 22:04:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d8967e087ac631a4fab9f1dafb811038 SHA-1: 80c4d51b1e6adf6e031c4d736539c99202c21bb1 SHA-256: 281ad5931869bc33c9de9bba1d9e58bec70f03dcd1f70ca2e5121d68fe0327d8
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as a link farm pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The embedded URLs, while numerous, are the primary indicators of malicious intent, likely serving as lures for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://mymango.ru/wp-content/plugins/super-forms/uploads/php/files/9f1ae3f5cac2f233dbf7b3fd3f744753/24799126841.pdf In PDF document text
    • https://sbufficio.it/file/18944981987.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160830e9893e24---noxaxavovemu.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7fdcbd9045---kevobeximonakigok.pdfIn PDF document text
    • https://loyallcanada.ca/editor_files/file/19585139614.pdfIn PDF document text
    • http://www.proyecpapel.es/ckfinder/userfiles/files/44410762453.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/xomapotaburomijinefo.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/eij7jamf80daerolgsuhpvpa5d/479105453.pdfIn PDF document text
    • http://kangs78.com/clients/66216/File/54970186069.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dce08d6dd5---21652490245.pdfIn PDF document text
    • https://loctra.net/userfiles/file/joderugajalibogexisomatim.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/7067ca5c2c9beb675e38eaa9bd0dd859/lofam.pdfIn PDF document text
    • http://roocenter.ru/upload/file/65087538354.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a01ec81f328---peforal.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/sifowuz.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/jonemifakopimavevugopuz.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/a99b1f862931c92831b5b7c5d8b35cfb/31071748019.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0e364cf9e---jepimakog.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/midulatofusupalobe.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/54189914676.pdfIn PDF document text
    • https://digireg.at/upload/38834489352.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/sujufezazukapanopogaf.pdfIn PDF document text
    • https://shindah.com/images/ckeditor_img/files/nodus.pdfIn PDF document text
    • http://bigpictureresources.com/userfilesbigpicture/file/romerokabutovavenazeja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=force+stop+app+on+iphonePDF 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_off0000ea5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA5A 17828 bytes
SHA-256: 863814165a2dff1e1ed1b5c01c0ae09a0b7d8a2cec703e6b34c5757aaad830e6
font_01_sfnt_off0001192f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1192F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013146.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13146 10404 bytes
SHA-256: 5e6cee99c959da2e1987607b85ace1df61b311700c2dfd9ec27f113b66a6fb9e