Malicious PDF — malware analysis report

Static analysis result for SHA-256 86793aadc1404bdf…

MALICIOUS

PDF

76.1 KB Created: 2021-09-04 06:22:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 82e349b863add1360083af122a71a83b SHA-1: 67c63119210a9fa9cc40c400e96b1ca2f28ff88c SHA-256: 86793aadc1404bdf7377998faca0077f7421d737ced3611156231be844469521
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the presence of external URIs and compromised CMS uploads points to a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c43bcf42865---26510748643.pdf In PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609d05baaf71f---limizivevexabigugu.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/49458726506.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/56848249162.pdfIn PDF document text
    • https://thietbidiensino.vn/media/ftp/file/vifopufases.pdfIn PDF document text
    • http://khocabien.com/uploads/files/59321647078.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/50681791303.pdfIn PDF document text
    • http://ituor.ir/basefile/chartermeinfo/files/sesiwugorabokuso.pdfIn PDF document text
    • http://generaldistco.com/images/file/37343036022.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/noxijuragot.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/9da32dd9422a4192969d88cad8977a54/fimoso.pdfIn PDF document text
    • http://www.gpkoaee.ru/ckfinder/userfiles/files/53269133249.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c01b9059b---nulobomubemolepilo.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/fiwaz.pdfIn PDF document text
    • http://metabolitplus.ru/files/file/lalofiwaruvomo.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/botukazatawibumotubewuz.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/585a268439ea598700278dd0e9304cc4/95611274011.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/8cd2b49ee505b0bdc65a31e993d4e49c/kipejexume.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/470b8e1f679d5b465c125c51d0285459/pamize.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/161083ab16b81c---roxadupepudelaru.pdfIn PDF document text
    • https://bursac.net/userfiles/file/bokiwiwanibelik.pdfIn PDF document text
    • https://emprenderem.cl/files/77294694197.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/29891431516.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079cb864fcd1---dexure.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=calculating+frequency+wavelength+and+energy+worksheet+answer+keyPDF 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_off0000c5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE0E 16540 bytes
SHA-256: 8fa6122f2bbd2ec3b33897691244a82828b3caf19095252d748430766b1984aa
font_02_sfnt_off00010828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10828 11388 bytes
SHA-256: a9265a964115e52ec11616d342e07b8c5f03fcb69e38331e64a4ab0663584807