Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b69c498c5ec5734…

MALICIOUS

PDF

87.0 KB Created: 2021-09-07 10:53:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bd90cb1a8329a9355fd59f71b1283cca SHA-1: cf053a36976e314a3ad94737d185733bbb3a38fa SHA-256: 5b69c498c5ec573470233e37c8ee28d124f163cee1c0490b9785383548f3d707
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document contains a large number of embedded URLs, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate attempt to create a link farm on potentially untrusted hosting. No scripts were extracted, but the overall structure points to a malicious intent to redirect users to external, potentially harmful, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://queure.ru/uplcv?utm_term=sonos+play+5+1st+gen+manual PDF link annotation
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16071a6df75a46---35858194387.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/zawomi.pdfIn PDF document text
    • http://yanarfabrics.com/firma/files/62097160675.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a4386ad5172---jesakedinajimiziwe.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/68627802120.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/fevewoworejosesagojefu.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/c6409ee9435c04d7d214d1a4318f5d13/fokonatesuwinaro.pdfIn PDF document text
    • https://www.aifimm.it/admin/inc/ckfinder/userfiles/files/14945280621.pdfIn PDF document text
    • https://hansenlight.com/UploadFile/files/7764059330.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160966cd4bb19c---55488548718.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c788af6eed9---nezexesamujekomemujuduno.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/rofokubaxumonosutumo.pdfIn PDF document text
    • http://mesterek.net/tmp/naxipuxogafebinogugunese.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/tuwadewin.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160754cc3a9122---webewil.pdfIn PDF document text
    • http://lblussana.it/images/file/rumamunugikojur.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16086c39f4f7c9---nomukinatujuwazo.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/8832025287.pdfIn PDF document text
    • https://rosettes.it/userfiles/file/49066424116.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/2450397f5dca7f73a262f0ea752321ab/2845071895.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac62568b796---3114430976.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/ridefowafisa.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_off0000ebfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBFC 10876 bytes
SHA-256: bc8d1baf9d42da9bb007a8c696cba5c978e6a6002bb2216a64f0998645e4f6fb
font_01_sfnt_off00010551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10551 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D63 18696 bytes
SHA-256: 5b2e3a0e24d15a37b8e608eba8cb4a9d518702d6214c16ae37882307b15e47db