Malicious PDF — malware analysis report

Static analysis result for SHA-256 21bbc87be1eb7828…

MALICIOUS

PDF

84.7 KB Created: 2021-08-11 14:53:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 57c3e67e148c75ad0b4522feb8582b8c SHA-1: 5ba698570a9e6aa14fc935798e61a15c412e138c SHA-256: 21bbc87be1eb782851371a10119168bc77e47d77d2dcd3f57560604608a78534
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a phishing lure, primarily through its extensive use of link farms pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the structure suggests it's designed to trick users into clicking links that lead to further malicious content or exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://actaviaserica.org/board/file/files/zuzuwafabudimojulofi.pdf In PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b55ce447d86---bolopigetelabitezigi.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/842cd1abe8a4cdc7ad05b85f5a3a090b/94689053452.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609119667366a---rixikugemorudukinele.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/42168181233.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160adcac1e0749---29937944023.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a2f1b48105a---63519457436.pdfIn PDF document text
    • http://residenceraffaellotorino.com/userfiles/files/59337795882.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/4e93a32d3a267943b8a75772a31e3004/bamajotesudaridij.pdfIn PDF document text
    • https://chptravel.ir/data/file/basigewogisotuwimigepat.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/61d3811f41e0585d5c40d648421439b8/35034256214.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc9534bac2---32113797737.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/17859968319.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/91678d037f2ba81ca00418d52d6bafa2/jezelox.pdfIn PDF document text
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/71093848951.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/j8tn0o0sjdu9f0qog0uo2i6ljr/sogad.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16079b2ff95d19---52115435052.pdfIn PDF document text
    • http://xn--12cmi2byac9cdhd0hra6d7bxkwbgj1gch.com/user_img/files/40688568237.pdfIn PDF document text
    • http://asokmontridental.com/userfiles/file/46054649231.pdfIn PDF document text
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/312a1ca28440886df4367417e311d5e9/xudiduwi.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/91640727389.pdfIn PDF document text
    • http://pagyesa.org/userfiles/file/20210808210241.pdfIn PDF document text
    • http://thebaileyfamilyreunion.com/clients/6/6f/6f45d7e5c9279c15d0bd3a3fa6949618/File/tadejavisajine.pdfIn PDF document text
    • http://maxidmum.com/images/upload/fck/file/pipatasazaruvi.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/11409220455.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=recep+ivedik+1+indirPDF 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_off0000e4d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D1 10168 bytes
SHA-256: 3e3fed95cdcb7e43b556e03ec749b926342341f06ae4b56ab8a29ad4b018d31c
font_01_sfnt_off0000fbb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000113c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113C6 19172 bytes
SHA-256: 9b9355552fbda4901b7002eb1d7a0f09190d5ef5ad9d1e86be5116dd9674cec5