Malicious PDF — malware analysis report

Static analysis result for SHA-256 10735f9bf18731ec…

MALICIOUS

PDF

81.9 KB Created: 2021-09-23 02:46:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9f283e29982b822d727e82acb6d016b7 SHA-1: 67edd1a58573fbabeeecd051dac53334adb1b8e8 SHA-256: 10735f9bf18731ec3558150bf30def038fe61d9fc65643d7115e2505fd2e2bc7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a link farm pointing to compromised CMS upload storage, suggesting it's part of a phishing or malware distribution scheme. The presence of embedded URLs and the nature of the heuristics indicate an attempt to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/dmto0808f1bjoaene63b5q37v1/5420851129.pdf In PDF document text
    • https://anninhsieuthi.online/upload/files/jipixevazekekipe.pdfIn PDF document text
    • https://teater77.nl/userfiles/file/bulapanokuxifijos.pdfIn PDF document text
    • http://chaputlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/35464533554.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/67044864115.pdfIn PDF document text
    • http://flemingdecal.com/uploads/assets/file/14997713027.pdfIn PDF document text
    • http://vector-food.com/userfiles/file/75947125041.pdfIn PDF document text
    • http://eastcoastbiker.de/sites/default/files/file/80452174332.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/6966801878.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/82646843521.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/mt538sdo23l2mmidbk090b5gh7/rusitaduradut.pdfIn PDF document text
    • https://nexusmediation.nl/files/fujenuxixubonulewesulug.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/luzemuwavabusevupobobodo.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/e4ed13c48ede0077385224bf1ed6dc64/koduwitawiko.pdfIn PDF document text
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nemamasuburarovilelinor.pdfIn PDF document text
    • http://resortvillairene.it/userfiles/files/leburufapejojujigazebe.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/7ee49ea2e1438f8d6f91866d365f1995/gosafovorib.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/1d2ff68aebd2fedd2bd06d00f6234aa1/92865269868.pdfIn PDF document text
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/venidiwakinefumufumubixug.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e86ce9459---1640668513.pdfIn PDF document text
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/42270117100.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161456ca749dfa---depep.pdfIn PDF document text
    • http://elitacasa.it/images/file/woxaxefivejuxonubevew.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/wumutifimepefifodif.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/siguziwajumanidewew.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16140338aa3c3e---sodogigip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=download+play+store+services+latest+versionPDF 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_off0000db69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f380.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF380 10776 bytes
SHA-256: 666cafb706a8a5750f7ab846b02aa94dc349b602ea1adc640b4109ee7c23d38a
font_02_sfnt_off00010c81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C81 17328 bytes
SHA-256: 03d901015148a603a0e5b1152dc3f73738448294432492596e3da1fd4bae43d1