Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb3f8f3b88a55365…

MALICIOUS

PDF

76.8 KB Created: 2021-09-06 18:55:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c77a7a7d218563777e9b15880b55100b SHA-1: 04316c47e81a8bde78612d0eb3c56f70a4071fd2 SHA-256: bb3f8f3b88a553650bc7d87d9f02c8f27458f3995010fb752e4ef46bf8189304
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious content or phishing pages. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/i64pa5qehpint8odhlg7rm82o4/zexulojurovibo.pdf In PDF document text
    • http://piemonteforyou.it/userfiles/file/marezamapexonif.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/amdi5bnal2m1qka7ods15emj31/90009348279.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/vatudopuzupog.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/ik6aanhcinjb49tbgvgegi95kg/3269788349.pdfIn PDF document text
    • http://railwaysrailroads.com/upload_files/files/tudopasude.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/35269fec854d5e3ef5482123a29753c6/gudelupinuvowifepa.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/kcg49ja5siesu9kmh4234k4llj/sabetamidepuninoriri.pdfIn PDF document text
    • http://ecofincas.net/ckfinder/userfiles/files/32121459576.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4c609773c---65813232746.pdfIn PDF document text
    • https://airbays.com/userfiles/file/timekakonisenaziwedoxowu.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a72e7734a24---8862267887.pdfIn PDF document text
    • http://dagmar-e.de/userfiles/file/dibonanefotibelerize.pdfIn PDF document text
    • http://seamacros.com/upload/file/jinajumogevapox.pdfIn PDF document text
    • http://bm-shower.com/userfiles/files/mixaxitelerexurudemetevaw.pdfIn PDF document text
    • http://oletrans.sk/editor_uploads/files/26389290494.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/64685220873.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/58291324173.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7bf87ddbf---66901142290.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16084a20f41a06---75172200590.pdfIn PDF document text
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/0ba79324e953ac6edd8c33e5ae06cb95/20598988326.pdfIn PDF document text
    • https://yourownadviser.com/ckfinder/userfiles/files/33858073783.pdfIn PDF document text
    • https://lienlacanien.com/img_pages/file/butod.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/777455179.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=congruent+triangles+hl+worksheetPDF 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_off0000c903.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC903 16768 bytes
SHA-256: 8e58a723e9f5ba902ca2dc96408b54f03f13ff810fb3b63dbe1432d01a1a9f57
font_01_sfnt_off0000f49c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF49C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CB3 10696 bytes
SHA-256: 13b318abb2ecdc21b9dd34923269dce1edcc7e1f165b52620142474153fce51c