Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff8d6ef264590c29…

MALICIOUS

PDF

69.8 KB Created: 2021-06-24 11:09:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 3c5aadb05371f9a9fc7d08799d27b961 SHA-1: 5eaacffb7485bd1cdca385d7bae5c0993e1de461 SHA-256: ff8d6ef264590c2961e0f27669e4a172632c8f3d2ed899ce709922c7d9061978
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The document body, though heavily corrupted, contains text related to educational materials, which is likely a pretext to trick users into clicking the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://garglob.ru/uplcv?utm_term=geometria+y+trigonometria+baldor+3+edicion+pdf PDF link annotation
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/gbudcuvq2se1pdu12tmbfmreqk/63083033085.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b89dc60f509---kafotokewepugiler.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160abff9552976---96880408690.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/45263727757.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210617185626529.pdfIn PDF document text
    • http://mpti.ru/userfiles/file/xomiguwimapadofi.pdfIn PDF document text
    • http://laclonghotel.vn/upload/files/bagigotebe.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/jilupifugokomumewepi.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160aa86d7b0e2e---53392942252.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/fhotsc7tmuhq4ln7i4fveh1aie/mipigugetutepozanosiso.pdfIn PDF document text
    • http://kgmda.com/upload/files/76154312061.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8eada17cef---bunobepab.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609050a9ebe9e---157134184.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/3bf2434572ee5ee4993bb5171f765415/tuxonutufabololirefer.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/vrmp5s2tpnpg2uu6uqrk9r5q9n/57605007786.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF5D 5736 bytes
SHA-256: 2323c4697440a95ba07ea8afd49725fac4504eeb96b7f5b63d1b7beceb21a415
font_01_sfnt_off0000e2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2DD 11476 bytes
SHA-256: f855caaf28dbc0dd8b9e5338c2a7d6482861f62d5e5bac48cd568d2a8efb3c57