Malicious PDF — malware analysis report

Static analysis result for SHA-256 5035d9d6714ac6c0…

MALICIOUS

PDF

148.9 KB Created: 2021-09-08 00:01:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3a8340b21c668079d57f5109bbb65ca3 SHA-1: ebb01b99a5134cd0ce7e866321447d9c7e04e4f0 SHA-256: 5035d9d6714ac6c00160b564f6fd3f43caa4ba9749432f7be837ccf00937f1d3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to other PDF files hosted on compromised websites, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery through these linked documents. No scripts were extracted, and the document body was unreadable, so the analysis relies on the heuristics and URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://ketchas.ru/uplcv?utm_term=gone+with+the+wind+full+book+pdf+download PDF link annotation
    • http://zsdbiopharm.com/upload/files/zuxal.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/a3c849373947438ac8089df1dee16bfc/97326717425.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210813105757.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160abbc06d9aeb---jixanerovivuwiwita.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/b1f514a51e83a35640bb1fa1db283a43/gewopapixu.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/478a3c803d8bcac0980cdc3e2ae2e5a4/tijiwizuzunipe.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/30766944fbaa2a8231d27d7254413a8c/95926803686.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/kofoz.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/julojij.pdfIn PDF document text
    • https://megalightgroup.lv/uploads/files/57329894814.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/gamomaxat.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/worinodixepifidizob.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/81095724476.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e2a20bae8fa---xijatazugafesadi.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/3091569182.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/a01662d54605bbc94f7b00041d50b03a/48551751521.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/kukafodokonil.pdfIn PDF document text
    • http://xn----7sbndn5at.xn--p1ai/uploads/files/reruwobekuwuniw.pdfIn PDF document text
    • https://malayalamfoundation.org/admin/my_files/file/86133049702.pdfIn PDF document text
    • https://leifs-auto.dk/images/file/75209443605.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/73968225369.pdfIn PDF document text
    • http://skyline64reunion.com/clients/e/ec/ec378541aa9b73e2b99de5ca5545ec21/File/74499408362.pdfIn PDF document text
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/ketuvonuzepesanakagazo.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/5dbad0d935a1139c31ea9462733ded5c/mujekuj.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_off0001e420.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E420 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001fc32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FC32 18640 bytes
SHA-256: cd89bb6c090c277a7364eb9cc4b6d4e5538af7c02645717114d30418767c6615
font_02_sfnt_off00022cf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x22CF6 10784 bytes
SHA-256: a175dd1a2b58b78fbc17b1317cc01f0aa6cf9e0cbd164ab8fc5188b6538c30ae