Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cdb5ab5209e22b4…

MALICIOUS

PDF

83.2 KB Created: 2021-08-15 05:53:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d8f0db0cfcc43155765b101020689e4d SHA-1: a085b21884e824ef0d732ccd4971dfb7de80124d SHA-256: 8cdb5ab5209e22b4405ca1fc2b7c4b57054d0647886e6bd19660e909a55ca4d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of numerous PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM firings indicates a strong focus on external URL redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://bellina.pl/userfiles/file/tisozexasedumidiwigozag.pdf In PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4e0123c34---semibomupujid.pdfIn PDF document text
    • https://digireg.nz/upload/87613613662.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/h7hvhpmj81skn0a40qjkc67p7j/37120060556.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a945801afc5---5233783104.pdfIn PDF document text
    • http://ramz-alqassim.com/Files/files/lerupiwanan.pdfIn PDF document text
    • http://hopkinshigh62.com/clients/7/77/7764523e397120ad9b09b1da26998858/File/gefegegoxidafeserogi.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160792ccbc7faa---disolupumonodanesulorikur.pdfIn PDF document text
    • http://kaizenlife.com/ckfinder/userfiles/files/17582882842.pdfIn PDF document text
    • http://haohanlegend.com/Uploadfiles/files/xolifimivapexogev.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16089f9de2e578---80032768813.pdfIn PDF document text
    • https://aviatroglo.fr/IMG/file/vulosapigogututa.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b4fc60b2762---10838936307.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/5d63a48efb3e75e5f47a3ed79cac3730/59450518336.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ddadb5b7bda---fojizisug.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/71784563123.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/bekinofujezepum.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16090d4831e1b5---gidozesiwajikemusiwunewoj.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/q6gif60h8okgjd6ba479tqah6f/zinebewovavipuve.pdfIn PDF document text
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/9640325e3adee95e0f3af498e76ac600/gewutukumovuzixe.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/30096873997.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/83764800876.pdfIn PDF document text
    • http://constantemail.com/userfiles/file/162268445763800672032.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/7cfcde12da6161e325806bf4ccbcfc4f/puwixe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=adjective+preposition+combinations+list+pdfPDF 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_off0000e0e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E2 11100 bytes
SHA-256: 4680660110f70fd9c3657f7d2a4e1dc390e90deeaf60713a3c25f5bea0d764b0
font_01_sfnt_off0000fa7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA7A 16560 bytes
SHA-256: fbc6f9b14b494b8702a99e3054d8b7bc2d27e79f757f778f6254148dca222ded
font_02_sfnt_off00012590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12590 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1