Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c77d9ef1f57c306…

MALICIOUS

PDF

101.9 KB Created: 2021-07-29 22:43:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2561b46ed18b60e028bdbcd3b8fb8a44 SHA-1: f03dca5588e0046c5d99dad875106dbb587b9260 SHA-256: 7c77d9ef1f57c306423f3544e51bd994253c037e2832b6fbcc8b9cfd2aba0810
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm on potentially compromised infrastructure suggests an attempt to obscure the true destination or leverage existing vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/8267810d747270aa93c0b0a6f215cc7a/71286981980.pdf In PDF document text
    • http://rchs1964.com/clients/5/58/580abc73d3aac4ea3a2bdd7c75327783/File/toneworijotijoxuxatu.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8c9c3f3df---ranodijof.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/12790335976.pdfIn PDF document text
    • http://ippon.lv/uploads/File/62457197537.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607b3d3eca16f---fuxid.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ac80a1d65---tujakutipa.pdfIn PDF document text
    • http://vonschickenconcord.com/uploads/files/duduzabosupej.pdfIn PDF document text
    • http://yizhu580.com/ckfinder/userfiles/files/pizuradibagolowunutoxevep.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160e864bc191a8---96575853234.pdfIn PDF document text
    • https://srmresidences.com/images/bulk_images/files/loxija.pdfIn PDF document text
    • https://netpage.info/userfiles/file/85337046055.pdfIn PDF document text
    • http://aven.su/userfiles/file/fugap.pdfIn PDF document text
    • https://tagoproperties.com/ckfinder/userfiles/files/49890671758.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a7c14b91d37---lusowigasuka.pdfIn PDF document text
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/3146186491.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ccd068daf---89624109218.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/54428615265.pdfIn PDF document text
    • http://industriefotografie.ch/userfiles/files/buvifesevutatesif.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/b276d9858f2e410b1cf734fa3ffa1d93/widumuguwitisuxat.pdfIn PDF document text
    • http://teknis.it/userfiles/files/68214415708.pdfIn PDF document text
    • http://innotack.com/userfiles/files/verivo.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/moresujonolanunaka.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/negonejapuzutarisofi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=create+drum+beat+abletonPDF 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_off00012c4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C4D 17652 bytes
SHA-256: f676e305cb2e7c513a4aa836c70a4bb6663d3c349dce5f633863e2fff29655e5
font_01_sfnt_off00015a67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A67 10420 bytes
SHA-256: 725a22280f907eac02c7b450b5b9d296c1749fbecba40e8e432af1f9e77b62ba
font_02_sfnt_off000171fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x171FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1