Malicious PDF — malware analysis report

Static analysis result for SHA-256 c31818ed4ef203ac…

MALICIOUS

PDF

80.8 KB Created: 2021-09-05 21:06:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 2fe824b522b5bcb3c0148ee11891df42 SHA-1: 0ebb56d90a5cdd0f1116504e8d8e10ec35f21918 SHA-256: c31818ed4ef203ac90f164a81077fd57534ed698b8c28c295afc28b81c87047e
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple URLs, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL analysis point to a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612360f906d7b---tijiwamudupaxamure.pdf In PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/c67e188d4a4f22311a8b803bb580f9e8/18256610403.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/11803853190.pdfIn PDF document text
    • https://zhansq.cn/upload/file/wadasidojir.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/f1df722422958cc9c14f9ecb312bb2d9/pojejemiveletebudepu.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c9f59050460---32070655728.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082f9b8ade5d---3472682166.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/3354aa209169144d18cd8d5499100a16/44772718536.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021082318305073499.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/tupupatigujewevovij.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608971bdb3c55---40424677730.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160865dc24c87c---21669283827.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160862c3489e0a---bobope.pdfIn PDF document text
    • http://kd-council.com/upfile/files/segaruriloxarerati.pdfIn PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/pixojarasopuvabeko.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/13392066963.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9615dbae8---18842731598.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/2021060106344669118.pdfIn PDF document text
    • http://lehnerkom.de/images/uploaded/file/leganefosixedenapuvisab.pdfIn PDF document text
    • http://bastola.org/userfiles/file/73805400223.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/sapulavafolafoz.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/numasorebe.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/51609503829.pdfIn PDF document text
    • http://conniecorsentino.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tatojibozuresurapivimi.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612b680ad06e0---64502202037.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=sistem+parlementer+dan+presidensial+pdfPDF 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_off0000d91b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91B 16856 bytes
SHA-256: 2e2ea3fbe6b075b58e16747c208ba5b218dce5510c8cc9b738bc3b72245194bc
font_01_sfnt_off000104c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C1 10612 bytes
SHA-256: 6a4b10b16c123bfa43e5d50e8b90c70f1e95a0ce4a0008ac0ea81b847054f232
font_02_sfnt_off00011cf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1