Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8d709ff6667726b…

MALICIOUS

PDF

75.9 KB Created: 2021-09-03 05:13:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: cab6b5a7c33ed423b19b5525fccb72a1 SHA-1: 78f365b1e993e6e1b0b93434eb801426d9a5a4be SHA-256: f8d709ff6667726bf77ff2a118587562344ff378f8f194de0b2a17d3c23057c2
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. It contains numerous links, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/50b9120c0382b01682ec909afd16c784/dapawijolezosudamis.pdf In PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16094037b82706---wulirimufunova.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/bunidapedituzuni.pdfIn PDF document text
    • http://www.prieteniitehnicii.ro/documente/file/vimujupevetuvik.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/44116649119.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/61afu56ukfq3kcarecmca7ku46/narudo.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160dda78281fba---37201035532.pdfIn PDF document text
    • https://bauarch.bg/files/bemetitagavewugozepu.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb52c734a6---xupekedulasidapebala.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/simf7kkatgmr87s70ribdpltg1/difeloj.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a44f9cec4---zegefunotu.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/2418b76f74f8536a0e26b5f69dc0338b/forabuw.pdfIn PDF document text
    • http://ubest.ru/images/file/dawedaj.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/vufikagurudajaw.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160b2455765146---99728404879.pdfIn PDF document text
    • http://elturo.ru/img/upload/files/28106517909.pdfIn PDF document text
    • http://luxlustry.ru/img/upload/ludigepetapawebimujos.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ab6a00513d2---68413922573.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/nabekelaxegukarima.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16079049cbb8a6---91487998002.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/a47168cd12886b78751039d67c8f8ad6/mekixokuriwifu.pdfIn PDF document text
    • http://shosholoza.de/file/18448783439.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/rubefofosakuwobinobavaz.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/at3c4id5es4nstercvshk1d282/barusekumuxigesif.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/folakuduwigarinituwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=compound+inequalities+word+problems+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_off0000c2b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000daca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACA 17564 bytes
SHA-256: 7a1c1c90a39c86ecff754219e838a6671225d5e0918b6f47e1e0be806b5e95e7
font_02_sfnt_off00010804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10804 11164 bytes
SHA-256: 37c2f79acf561c25254fce91a6e10ae7a011feae548bc59a1b8fe28a9a24aa22