Malicious PDF — malware analysis report

Static analysis result for SHA-256 7500b65644f16962…

MALICIOUS

PDF

73.9 KB Created: 2021-09-07 08:34:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 44837e3e89cd568a8ca0ffb0e2ef8e0c SHA-1: a4d31b80d0a1509b2db6c6c80727129a3f3768cd SHA-256: 7500b65644f16962741a8fe02ad9ba11b9c4ba24e64f79cc3c0c7af6c90087ff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs are likely used to redirect victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba38ada2860---gumamo.pdf In PDF document text
    • http://sun-green.nl/ckfinder/userfiles/files/97701969299.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/dolevonexezamemenif.pdfIn PDF document text
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/89885144974.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1611aa5882c724---detutegukaxukibita.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/51318291382.pdfIn PDF document text
    • http://amphorabeautyclub.com/campannas/file/37118663302.pdfIn PDF document text
    • http://grupophi.es/uploads/files/84273273227.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d25b56effd---kumavijibabuv.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/xizuginikamuzatuzesem.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090998e372f4---mowija.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f35baea36c---begajiwosawipuwaximijudif.pdfIn PDF document text
    • http://katachizu.com/img/news/files/tozebudo.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/1nl8r46rpmjpemhsbggbtf0i82/dutuwizifumexozunuvasenug.pdfIn PDF document text
    • https://samarpanbharat.org/trila/userfiles/file/podekomezujadur.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160819f2b3de3e---vafur.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16116fca86c919---sulepemikubizen.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/sq00pn9gopt8a1qgo47acsup0k/sarow.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/brc3is5ucrdto252176akbrb6d/bojiva.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160f65c3c665ed---jiniditatukobofu.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be9cfa10109---56895556404.pdfIn PDF document text
    • http://laihoawedding.com/app/webroot/upload/files/37795022020.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/t64g4mc10eda3g2gne3q2d7nb2/66631856235.pdfIn PDF document text
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/12479306883.pdfIn PDF document text
    • http://smepil.com/ckeditor/userfiles/files/jafoguserumiresivamasow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=transfer+and+transformation+of+energy+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_off0000bec1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEC1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d6d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D3 16304 bytes
SHA-256: 8931b4630871d0d899f41d7734366f82daedb90fc505f59559bae0ff85da8d96
font_02_sfnt_off00010081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10081 11008 bytes
SHA-256: 27b1450207862cb483f2caf231623609de5db24a0e613e8a6ffc161fde8e8faa