Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4931e6430c7508a…

MALICIOUS

PDF

78.3 KB Created: 2021-07-01 10:08:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6252b2ba074fa4dbce19fb126feb4452 SHA-1: f305550026c83d07ae0b1e9e2e5f96b88b63877d SHA-256: c4931e6430c7508acf2f490b60b41a6d2d4c1f8ccdca5061b25ebc97599bb9c7
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, a common tactic for hosting malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farms suggest it's designed to redirect users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/5fb4f644488edde07be683ef296e0cca/gotidamidotinu.pdf In PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/40813624261.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/e937be61ad4f0c83efc076ef2d242356/wasexovegijupapumozusug.pdfIn PDF document text
    • http://airsoft1.ro/files/file/judubenaxazoji.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/gigojazipexigalen.pdfIn PDF document text
    • https://abicecream.ru/ckfinder/userfiles/files/nanofabaluxaziwi.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/57997855540.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/jltigjs1o0oetmrk7rvbmgk19e/58159612345.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/d14aadf043b7d6a8e988e3ca453b491c/24622861246.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/texati.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/59495832667.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a859bde4ff5---66376694277.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/15170220929.pdfIn PDF document text
    • http://donghocasiochinhhang.net/uploads/userfiles/file/domofeguj.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/6687a0e251c67ed176f83a1b244ce456/gojexokobiwigobopem.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/s3kc88o7mmo9u6vikkedcammk6/sejogupujuxez.pdfIn PDF document text
    • https://termofriz.rs//files/puwagofitumunu.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/dhot40m1o8cloh8fkqj7glgp8p/luzupufi.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f2804fad0---3168788735.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/6459cf4e8cfe38bff2b8d039bfd82634/33077650078.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/997328ea36528a81ab83199805e04383/24008102698.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/nalobonikigeza.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/44086644585.pdfIn PDF document text
    • http://iteequipment.com/clients/65150/File/59880493991.pdfIn PDF document text
    • https://chauphongasia.com/wp-content/plugins/super-forms/uploads/php/files/rltth4q3a8684amm6mgdegho1s/rufemux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=pride+yourself+on+somethingPDF 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_off0000cb95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A7 17532 bytes
SHA-256: 909251b8112af528022b283122ee47853426b5c1e4c11c43fe8912f18fcf6748
font_02_sfnt_off00011159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11159 10856 bytes
SHA-256: f3c3ddc8cbc8d9f1acb7c77e55310d4367bb7e9c29641ee83b4c0ac30d3cec8b