Malicious PDF — malware analysis report

Static analysis result for SHA-256 079cb9b18d58fb72…

MALICIOUS

PDF

81.3 KB Created: 2021-09-04 16:52:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6a23cb177149550fd2aa4d2ca9878102 SHA-1: 5795b80d523fdd06ef5fa25e3afd5b1e9e5f8eb5 SHA-256: 079cb9b18d58fb7249a54de4d6190323920563168b42926116030de3be8bce8d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to potentially compromised websites and disposable hosting, indicative of a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but containing embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5f6573d31---xisuz.pdf In PDF document text
    • https://greenfins-thailand.org/uploads/file/gekibizodomiwisumexajok.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d3f77a4a5dd---woxenif.pdfIn PDF document text
    • http://muzycznescyzoryki.pl/userfiles/file/nupobetadevazujane.pdfIn PDF document text
    • https://media-get.com/userfiles/files/savud.pdfIn PDF document text
    • https://manajrgvaaradhi.com/cms-uploads/files/pebenebapim.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/26913677585.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210808055859.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/tuxusurogawowamoga.pdfIn PDF document text
    • http://homeshopeez.com/uploaded_files/userfiles/files/retuvexudoratabowim.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/dekosumafenoloporo.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/pixejegaxuwebunesaxilojen.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/ece203c77256cbbfbe309fa95d72f573/kofosekadagagujikomur.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/54d475813c9f5427955335d424bd5319/tejelofomugukuwafixor.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/0ed98e0080bc5f33d9bb4508dff0da89/2824398600.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/77985099963.pdfIn PDF document text
    • http://juhaszautovill.hu/userfiles/file/nojiruda.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca04538409---bonana.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/61289384397.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=free+phonics+worksheets+second+gradePDF 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_off0000d533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD533 18976 bytes
SHA-256: 841f24d2e34a37f49ba6f2a387e181eeba9f21d0f8d051152f7e5d76883f868d
font_01_sfnt_off00010653.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10653 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E6A 10904 bytes
SHA-256: 5afa5335db292d849a116535b6c229a13efe0e96abfd1c0da87b9d13652095a2