Malicious PDF — malware analysis report

Static analysis result for SHA-256 331b8cb350d2a09b…

MALICIOUS

PDF

88.9 KB Created: 2021-09-01 19:26:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 50626ae97d3701ca4b54274bf002ff8e SHA-1: 5a1286a9d72eae8b1c2645895db22e79e8872b4d SHA-256: 331b8cb350d2a09b9e98d7d71ff65201b477a7185461c82f2c92524014630e3f
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites, indicating a link farm designed to obscure the final destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates redirection to potentially malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://pixomot.ru/uplcv?utm_term=fly+past+simple PDF link annotation
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/e446cc939fb6ed1daed09d6ce60f6934/xofofirifuxota.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/81836041c74d75c18b88f2f89c805156/fagezoza.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/b48ahj5ej9aoepqaj2cg5m3m83/lavamome.pdfIn PDF document text
    • http://designklasse.de/ckfinder/userfiles/files/12300846504.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/51024894729.pdfIn PDF document text
    • http://woorymart.com/userData/board/file/niwidobewejomukebi.pdfIn PDF document text
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/5dad1bcc5e190d54a5b01c0bb3549da0/30485537514.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/radiwunevorixugatapikusap.pdfIn PDF document text
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/p2vr3scuouuesih09748r04846/biwudokununo.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160715946555e8---56161153066.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/65628c13ea57673561832889421fce23/fometop.pdfIn PDF document text
    • http://kpghomerepairs.com/uploads/image/files/73952257186.pdfIn PDF document text
    • http://chanakol.com/ckfinder/userfiles/files/sopuw.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/duros.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/ed3e19852ebf88631b0a611f28110c4a/nanivav.pdfIn PDF document text
    • https://indirimlipin.com/calisma2/files/uploads/26993157952.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/zineziga.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a432a141473---lafuj.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/4f297154be76c75c5b4883cafc4d66a9/81128728790.pdfIn PDF document text
    • https://www.passion-rnd.com/upfile/files/2021/06/29/xogadunavokoroxiju.pdfIn PDF document text
    • http://tpokebar.com/uploads/files/69142554787.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/60326328009.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16102c24db2801---9073277407.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a6f327a55---kexijisododivakodufenu.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_off0000f7a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010fb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB6 17888 bytes
SHA-256: 4552c902ce75e4d7116275faecf1df31e3994ae0ff512a9084d7f74d6a6958e2
font_02_sfnt_off00013e60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E60 10180 bytes
SHA-256: 0e5fe22d249a74da96a58725d39c0d34aaec2e558d53d4a6110478ef4e8a355c