Malicious PDF — malware analysis report

Static analysis result for SHA-256 84645f0eec871ab8…

MALICIOUS

PDF

71.6 KB Created: 2021-09-05 09:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2baa79c6fed43843e9af94ef88c26b47 SHA-1: 5ea5b5494796ac7c2b2a491e19a085c941a35d78 SHA-256: 84645f0eec871ab807b19600c27490adcf49d01d41be8d73ddd76747fb5ba9fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous links to compromised WordPress sites and other domains, suggesting it functions as a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://crysiq.ru/uplcv?utm_term=clinical+biochemistry+book+pdf+free+download PDF link annotation
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adbee31c7ff---92624069347.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160d310941c316---firopavosize.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b30f44a97f5---37572271727.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/7757b4ed117f3f60b593aced7fb36775/7726933004.pdfIn PDF document text
    • http://renovator.cz/files/file/gewakisawek.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/10062661070.pdfIn PDF document text
    • https://badeluxe.com/userfiles/files/14495106729.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/hpbjahlrut0glb7l2e55j3atp1/27591366621.pdfIn PDF document text
    • http://iphysiology.ru/upload/66614187837.pdfIn PDF document text
    • http://challendor.com/fckeditor/upload/file/rababumifurumuboj.pdfIn PDF document text
    • http://evola.it/userfiles/files/pisiveruz.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083cd35bc723---zuliraferodewiraluwur.pdfIn PDF document text
    • https://apz-arte.com/ckfinder/userfiles/files/27846570291.pdfIn PDF document text
    • https://conexus-study-abroad-travel.com/ckfinder/userfiles/file/66265469082.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b857bcd9fc2---94768319477.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/81495541433.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4107dd64bc---nalis.pdfIn PDF document text
    • https://ubitanduk.com/contents//files/gokimokijuwo.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/lo350et3hlhe92a83m7aekulr7/50127108487.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/87500245999.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/8487552949.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305f570ae91---91107183789.pdfIn PDF document text
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/15692225966.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-7-19/20210719141516944386.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/160e4385dab9b5---savusefejib.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_off0000b74f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB74F 11348 bytes
SHA-256: 1d0846bd513103d2421c727df5299bde74d872c06ae984feec50755d9a83943a
font_01_sfnt_off0000d1b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1B1 15396 bytes
SHA-256: f362ab9581bc0019f67c1191478b88a6aa3592f1ecce66b4b0ea584debe4a092
font_02_sfnt_off0000f8bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1