Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6bcf1f9bec57028…

MALICIOUS

PDF

85.0 KB Created: 2021-06-28 05:12:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 77505ff8894c03cc4184de3fa14d2fa8 SHA-1: e4bdca4821162f21b9de33b1b4b2fb494e4906cb SHA-256: d6bcf1f9bec570288bb1e23f2aa7e65206514f6ec95a114dd9f3542ac048a9fa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern. No scripts were extracted, but the overall structure indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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=critical+thinking+test+questions
    • http://x-site.by/upload/editor/files/vusebabidomifum.pdf
    • http://becucci.it/userfiles/files/tofakoxodelozexokagomajit.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ada1c867f85---18204029941.pdf
    • http://meandnetworking.com/ckfinder/userfiles/files/90008273554.pdf
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c0564ed77---gimez.pdf
    • http://janandpoos.com/clients/872640/File/10361777729.pdf
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/c19a54505fae5f9fd6aaff5be44da083/37508655664.pdf
    • https://jerseyshorepirates.com/userfiles/files/27642730665.pdf
    • https://feng-shuiworld.com/userfiles/file/finezabegusunow.pdf
    • http://absolutelyneon.com/userfiles/file/68069039141.pdf
    • http://allmedicus.com/userfiles/file/85086824490.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/k0fpl0cv5l403nivmiucprvac5/wawinabewasi.pdf
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/68663054552.pdf
    • https://briljant-maleri.se/UserFiles/files/88663670166.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/726a0735c96322d8fac1ef335f03ae20/61742263526.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ec7547acb---vakimav.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160983e0a30e67---puzunilonek.pdf
    • https://gretajensen.com/ckfinder/userfiles/files/56294253018.pdf
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/f17bcf7b0a6cff52f94e5493d5b39e17/46483687027.pdf
    • http://files.ibiza-ferien.de/file/rasizesu.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a2eb5851194---guvaromumuroxilolesor.pdf
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5bc35a39b4---61454591844.pdf
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/aeeaaf1aa46e73b5a830ee038307ded5/1462727514.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eabc.bin
230ef76f46c051bbde6a3fd8d336956d300aca937b4bb27cf24cfe81e3f5b649
pdf-font-stream PDF embedded font (sfnt) at offset 0xEABC 10880 bytes
font_01_sfnt_off00010393.bin
86fdff8a848917e928954f180ce53d8310a745f2fdafb57c6ac3a6c8ad9bc82b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10393 16828 bytes
font_02_sfnt_off00012ee5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE5 16792 bytes