Malicious PDF — malware analysis report

Static analysis result for SHA-256 664f82738338a3ee…

MALICIOUS

PDF

69.1 KB Created: 2021-09-20 01:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fce6fa26b2de6a18857fe369bcd877c9 SHA-1: 969f77dc43b4fb8d450747e879dd1919acef1479 SHA-256: 664f82738338a3eeb42f5606a8d2720128fb4bb9fa67a3b91bd072ae05c0a718
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it's designed to lure users to malicious sites. The document body is heavily obfuscated, preventing a clear understanding of its specific content, but the overall structure and heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://nomylo.ru/uplcv?utm_term=psn+app+download PDF link annotation
    • https://nevjegyzek.eu/uploads/file/wukitaresobivixuzofux.pdfIn PDF document text
    • http://poaglasses.com/uploads/files/202109071755395312.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/16135c23dc80d9---19646970047.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/53973211278.pdfIn PDF document text
    • http://olgapolyakova.com/files/files/pidekegefim.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/8178830774.pdfIn PDF document text
    • https://ukmriptek.org/codeIgniter-hmvc/userfiles/files/vojuzikiwowafokomu.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/eb67783495d3d57be6f3ffee829d2530/10504749800.pdfIn PDF document text
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/rixozazodawegavarad.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/fuwegetamaf.pdfIn PDF document text
    • http://gonganmi.com/userfiles/file/40028108386.pdfIn PDF document text
    • http://podlahypilat.cz/admin/file/13421356070.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a9fa540a0---jetokajasokowof.pdfIn PDF document text
    • https://taperagi.com/contents/files/43490250640.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/xejixubo.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/21843161022.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/44315027528.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613daa12b50a6---15308496002.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/2b8c1ebaf64ff1e2d1b0349d120239cc/81876095186.pdfIn PDF document text
    • http://yoshitomo-kokubunji.com/jcfiles/file/78823063292.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/95544531220.pdfIn PDF document text
    • https://starfoil-mail.nl/uploads/wysiwyg/85935706259.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/xavajolixid.pdfIn PDF document text
    • http://globalsocialwlefaresummit.com/app/webroot/uploads/ckuploads/files/rukivup.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/gaxoxupisupovibekag.pdfIn PDF document text
    • 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_off0000b3d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D1 14576 bytes
SHA-256: 10a30e2704a890c37d989298304eeab81840011dd5b2e485973e559d3a87cc04
font_01_sfnt_off0000d87e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87E 10048 bytes
SHA-256: 07d0694b47b3c8aaaf20db943f9e4669dd6024a08ed5bf48063f4f1e3d8ee456
font_02_sfnt_off0000eef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1