Malicious PDF — malware analysis report

Static analysis result for SHA-256 53fa33c909b61d5d…

MALICIOUS

PDF

83.4 KB Created: 2021-09-20 13:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f70cbf55f6a6cce2387a7396ae2891cd SHA-1: 117c1661da5deef83aecb1dc977417ec2216ebe6 SHA-256: 53fa33c909b61d5d3aa464346b7f5c371a4780309b35714f9557a21f7487ccd1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous URLs pointing to compromised WordPress sites and other domains, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farm heuristics strongly indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://medvor.ru/uplcv?utm_term=how+to+hack+into+someones+snapchat PDF link annotation
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358fa3c8ca7---17049970403.pdfIn PDF document text
    • https://rpaxis.net/userfiles/file/58117074994.pdfIn PDF document text
    • https://nabijdefossa.nl/upload/files/55722047181.pdfIn PDF document text
    • https://pmfegypt.com/userfiles/files/88362925986.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/59060144616.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/69416809030.pdfIn PDF document text
    • http://midoriku.zaitakunet.jp/app/webroot/upload_images/files/56128921530.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/kabivoboxekupikekufoja.pdfIn PDF document text
    • http://co-wemart.com/careeruserfiles/file/89284671965.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161383b497e4ba---kaporotovu.pdfIn PDF document text
    • http://istihdamhaberleri.com/upload/ckfinder/files/labevukowaza.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210901_090751.pdfIn PDF document text
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xojorovevuzofo.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/bb72de570f7d4bc56ad8eabfa630078f/xelotodom.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/jjpo0s5ba118a18jt08ddc0687/42770288888.pdfIn PDF document text
    • https://rozynoklinika.lt/userfiles/file/penigujujuji.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613875748bcce---tavupuvizalotakuz.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/8497905601.pdfIn PDF document text
    • http://balashixa.inhome360.ru/admin/ckfinder/userfiles/files/73815738546.pdfIn PDF document text
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/rojor.pdfIn PDF document text
    • http://thaifilmind.com/UserFiles/file/37372732606.pdfIn PDF document text
    • http://yonezawanet.jp/units/24250/zcycom/files/xapes.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_off0000e23e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE23E 10664 bytes
SHA-256: 2b3e49b124702eedf10797d8eda6298fa487a35f3c8b5b5e6ed84bdb7c40485f
font_01_sfnt_off0000fa8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8A 17220 bytes
SHA-256: 808e7c1f1b6a297ae9037ba85adda3fe98802dc609441987a784c444c2402185
font_02_sfnt_off00012689.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12689 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1