Malicious PDF — malware analysis report

Static analysis result for SHA-256 9978b6f4f88fc35b…

MALICIOUS

PDF

83.8 KB Created: 2021-09-03 05:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 58099880f44bc6b236d514bebefe370d SHA-1: ecef092b7563f32cf6b7a45ae01a6dcab7d05c69 SHA-256: 9978b6f4f88fc35b6a32e439ae80fb254d94aaaa3e8d741c85019a53774343cf
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and ML classifier indicated high maliciousness. It contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious sites. The presence of 'utm_term' parameters in some URLs indicates a potential SEO-based lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://drafthe.ru/uplcv?utm_term=how+to+reduce+pdf+file+size+mac+acrobat+pro PDF link annotation
    • http://mdsalon.ru/img/lib/file/kirugozi.pdfIn PDF document text
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/rogib.pdfIn PDF document text
    • https://ingatlansos.hu/images/userfiles/file/waximagiw.pdfIn PDF document text
    • http://computerdoki.hu/user/file/livaxuvixomor.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021061903352230.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/cfcd95f9dc7898218625355a887d2276/62480425920.pdfIn PDF document text
    • https://mb-classic-service.de/userfiles/file/wuvamopavapipajuzoligunur.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/41233063259.pdfIn PDF document text
    • http://agisma.ru/files/pages/files/vebijejegog.pdfIn PDF document text
    • http://perfectionistpaintingnj.com/ckfinder/userfiles/files/60959579858.pdfIn PDF document text
    • http://4bx.pl/public/file/16519380659.pdfIn PDF document text
    • http://sorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/28306438220.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa88880de59---45786292573.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/xakemuferubevofasezilosof.pdfIn PDF document text
    • http://secretinvitation.net/images/files/66209363065.pdfIn PDF document text
    • http://terremeraude.com/userfiles/file/toxavefiru.pdfIn PDF document text
    • http://one9five.com/userfiles/files/41601305130.pdfIn PDF document text
    • https://verner.lt/images/files/zusuvova.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608b8690c2a23---85864629939.pdfIn PDF document text
    • http://firanywiktoria.pl/uploads/editor/file/60021029491.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210609_180621.pdfIn PDF document text
    • http://jessicarossitto.com/clients/7/7c/7c16b8c799dae9ffcd1258f31d6ff645/File/zovuximazamidijux.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_off0000e338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE338 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4A 17208 bytes
SHA-256: 2ff1fc65eee545baf6b2bddb5447423a0398e19d937b8837e4e2f1612c4b39d8
font_02_sfnt_off000127a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127A8 11056 bytes
SHA-256: cc880b4a92bce1b3f226faab789a43fce80356f317d00cb4d96006a53d7f51e4