Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ec40e135856d00a…

MALICIOUS

PDF

90.7 KB Created: 2021-09-16 18:12:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7ef66eca5b01ef983c0c16cf2cf58166 SHA-1: 9502423fc61ad585e5f9874fa6d8ce2b5ab394af SHA-256: 4ec40e135856d00a69ea38739682a87fb854aea560d1fb94dbb71f1226492b6d
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various websites, many of which are hosted on domains identified as disposable or potentially compromised. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest a link farm designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16130bb515f162---1691898049.pdf In PDF document text
    • https://nidi.mk/ckfinder/userfiles/files/xemefevotuzoruwewodin.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210904121212097.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/57909712251.pdfIn PDF document text
    • https://matharu.ae/userfiles/file/kaduronutatogesoxebubise.pdfIn PDF document text
    • http://skupka23.ru/upload/m/85902333703.pdfIn PDF document text
    • https://dawnraytech.985.tw/data/file/userfiles/files/76072793673.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/m09pi3dpuo58tpe8kjq2qboea2/pinupako.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/wawosizisidelofutamigenew.pdfIn PDF document text
    • http://cpils.com/userfiles/file/pukepunin.pdfIn PDF document text
    • http://lukinserv.hu/file/nagonozu.pdfIn PDF document text
    • https://betenagro.com/sites/default/files/file/73271873526.pdfIn PDF document text
    • http://klhl.com/userfiles/file/teruw.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/41491306523.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/vofewidal.pdfIn PDF document text
    • http://domosplast.hu/files/file/37967679857.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae0f1dbf68---85940873529.pdfIn PDF document text
    • http://artstudiodesign.it/userfiles/files/jorida.pdfIn PDF document text
    • http://fabriziocar.it/userfiles/files/sosifu.pdfIn PDF document text
    • http://nature-revive.org/files/file/minika.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132c6393dfac---lopuwidalatubesolakoja.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/29622372429.pdfIn PDF document text
    • http://nirmalapublicschoolerumely.com/userfiles/file/liwuposuxefulifagale.pdfIn PDF document text
    • https://zaragozadenoche.es/upload/files/34020935296.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=otak+atik+androidPDF 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_off0001000d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000D 10012 bytes
SHA-256: fc7caf396b8a9c0429e0b83f679cd83eaa08d6b9ce2510e9610ff099d5a41acc
font_01_sfnt_off00011661.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11661 17912 bytes
SHA-256: 1dd52cd8a7be95427c14a767b829ad8795af2bb6ed4141b571a4e8364b29e252
font_02_sfnt_off00014551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14551 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1