Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dbc1357fe64f64d…

MALICIOUS

PDF

77.5 KB Created: 2021-09-09 13:54:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ee1ce74f37f298956f4d4db3baa74b72 SHA-1: e3e53da2485563cb794f17fd796fa4976f3b6a13 SHA-256: 9dbc1357fe64f64d7bfa9698b68a13ee99c19854eda1bd0b8c3cc84deaf808dc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to various external URLs, many of which are hosted on disposable domains or compromised CMS upload directories. The presence of embedded URLs and the overall structure suggest a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://cructi.ru/uplcv?utm_term=the+western+australian+death+notices PDF link annotation
    • http://gyndoktors.de/ckfinder/userfiles/files/24308321897.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16130bf6cd438e---jadovusida.pdfIn PDF document text
    • http://veganogle.es/uploads/ckfinder/files/munesumuwesotunejiketon.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/zafijaju.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/54987601144.pdfIn PDF document text
    • http://www.tecnologycenter.com/admin/uploaded/fck/file/tisotub.pdfIn PDF document text
    • http://studiophotosfashion.it/userfiles/files/bufelowomo.pdfIn PDF document text
    • http://rafaelokazakov.com/file/lubetudufexeni.pdfIn PDF document text
    • https://mwasafat.com/uploads/files/gujelolesexotugudefovuz.pdfIn PDF document text
    • https://nucamsa.es/userfiles/files/39819757055.pdfIn PDF document text
    • https://generalaudit.pl/eurostyl/photos/file/83769791979.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/56737083724.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131356bb157d---tevux.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130433e549c4---47606691465.pdfIn PDF document text
    • https://gobelsprofil.com/upload/files/mopaseki.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/8809537457.pdfIn PDF document text
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/dozepewafanumikakugujigez.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/11538173326.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/kopovofifujagivutip.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0790d1192---jovizobapepidewuzelidepus.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/39560094585.pdfIn PDF document text
    • http://damosushipleasanthill.com/uploads/files/60402231798.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_off0000cb0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e31e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE31E 17552 bytes
SHA-256: 29c2016e624035d1a8960065cf293d99b22a91fd44ac9799d99ad5ba19ece39f
font_02_sfnt_off00011015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11015 10616 bytes
SHA-256: 5e8c2c4409cd44343098099248f30e5d8452695d0e72d68ff4d784c3472998b6