Malicious PDF — malware analysis report

Static analysis result for SHA-256 99bb721f201c3ff3…

MALICIOUS

PDF

75.3 KB Created: 2021-07-02 08:32:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 53849cc169748eccdc32b66c14dca48c SHA-1: d14d887e1fdc606f3b093a9f6550997981af8218 SHA-256: 99bb721f201c3ff3f2f25028a9599f6e18d8dddc2b6f6ebc91aaaa85e67e3fa3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised websites, specifically targeting WordPress upload directories, which are likely used to host further malicious content. The presence of these link farms suggests an attempt to distribute phishing content or malware, aligning with the Spearphishing Attachment technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/40d863cf82c469d2c722c96029733216/81972142803.pdf In PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/9d7508143269fc0e11aa6dd580fd4ccb/92655902706.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cccafc9a1b---13769830597.pdfIn PDF document text
    • https://myclubowners.com/userfiles/files/46228727974.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dca76bb312e---10058124579.pdfIn PDF document text
    • http://afslab.asia/upload/files/nuporasogelunegabubo.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef7ea611dc---28895953442.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/sonaninu.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/3900574678.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/33892312223.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160be674e200bd---74781411437.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093c93b30d6d---31586485662.pdfIn PDF document text
    • http://www.irrv.org/uploads/files/56771880776.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bf589b93b53---57367626425.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/eb9b96f7b33b83dc8141618bc4d215db/17231944746.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/gofewubiwepixo.pdfIn PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/65621872003.pdfIn PDF document text
    • http://mbcasc.net/imgs/file/nurerel.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/2eb9b96728e4905950d4463eeac3b795/gipudagavabetiloje.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/dagede.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607294dfc3eb6---24323181393.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/13242f241eb3099fc010e0f33e4d94c7/katawaxoralivamokataribuz.pdfIn PDF document text
    • https://legouic-peinture.fr/userfiles/file/futagemita.pdfIn PDF document text
    • https://unosms.us/userfiles/file/megas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=the+big+leap+book+pdf+downloadPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/adfd48cc82bc27976881a41149e2f213/60804496804.pdfIn 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://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_off0000c431.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC431 10692 bytes
SHA-256: 64a0f006ca53536939c5467657744325b5d9cb80f0d95e3e8801bb12b5dce115
font_01_sfnt_off0000dc36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC36 16752 bytes
SHA-256: 78f5bebcdd3d2c5978878b90ab7d26400a828d6462ccdaba687173f14cf49bbe
font_02_sfnt_off000107d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1