Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b81f7b8525574bb…

MALICIOUS

PDF

88.0 KB Created: 2021-09-01 19:51:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: dcff820402da6b3171e0d3c18884751f SHA-1: 009172eadcf6a8b7c0517eed1c80cfcb43a9b810 SHA-256: 7b81f7b8525574bbc97ccf85bb0ebd62054b83a92b81d1f291ede55f62ab77d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains numerous links to external websites, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://huntic.ru/uplcv?utm_term=government%27s+unfunded+liabilities PDF link annotation
    • https://polresseluma.com/assets/ckfinder/core/connector/php/uploads/files/taluxodepepimagibutep.pdfIn PDF document text
    • http://dlmberatung.ch/userfiles/files/kijejufodopowekubu.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/f17fafa1f0aa395256d3fe855a1c0eb9/zojakijiwewi.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9c4e57a11---minagagemobevem.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/0edf92fb16029b38a5d4335857b4a48e/zesaxakulinexikuworiruxe.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/24682457589.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/adbb5ef43293dfcab1b5e4be8d956fb4/58287898405.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609edba80ad18---xivisumabar.pdfIn PDF document text
    • https://indikino.com/ckfinder/userfiles/files/78985465872.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/451d1cf243345d916dcee9418320c057/dakegisireveguwesozexiran.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/8499827616.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/74948640351.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/fajapek.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/en8jtifu7cupch2m3v2kej6k5g/33130763411.pdfIn PDF document text
    • http://c-amc.com/upload/files/97842886070.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/7804db6ee569f71c23c36300f1f5fe3f/58908835159.pdfIn PDF document text
    • http://bidadapatidar.com/userfiles/file/14238473971.pdfIn PDF document text
    • http://resortcrimea.com/ckfinder/userfiles/files/xajuvubusen.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/87140705935.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fb9fd8a10---97109742460.pdfIn PDF document text
    • https://iword.de/userfiles/file/76540740654.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4824414ff---lexuvamirisufo.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081ad43f022c---lizedesiwonumusofopilot.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/28b1s8lqaca3opcirdstvsa5u2/ribunibuvunirakuxusofedub.pdfIn PDF document text
    • https://dprkoreatour.com/uploads/files/83576001856.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1611dbcbbc3ff0---47777095013.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_off0000f18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF18A 18500 bytes
SHA-256: e22b824a022466ae16a06e2d6bec3d79e1d0a3cd655085e6d75a1199e6638ad8
font_01_sfnt_off000120ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013906.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13906 10892 bytes
SHA-256: ae68b29be35a942b42ec975d49ebcfd16e4559b95b22ad14c6d4c0f1da6144fb