Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8c561c39d88b79…

MALICIOUS

PDF

76.6 KB Created: 2021-09-20 17:24:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9cbcf3880e822d6c8297c6ac69b04c61 SHA-1: 54fe666ac56e137d744c37d9a4f04f4eb327b512 SHA-256: 8f8c561c39d88b79bfe16bd3ad21e224267a4c2320ed3306f2739aefffe5a70e
196 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, and it exhibits heuristics related to browser extension installation lures. The document body is heavily obfuscated, but the presence of numerous external URLs, some hosted on compromised WordPress sites, suggests a phishing or malware distribution campaign. No scripts were extracted, but the overall pattern indicates a social engineering attempt to trick users into downloading potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://queure.ru/uplcv?utm_term=green+screen+apk+download PDF link annotation
    • https://cdmsig1.com/ckfinder/userfiles/files/dufetorovi.pdfIn PDF document text
    • http://adamslakeband.org/userfiles/file/52565287793.pdfIn PDF document text
    • http://www.larucheapain.fr/ljk/file/narelotelajofu.pdfIn PDF document text
    • https://loonbedrijfschimmel.nl/userfiles/files/22663550705.pdfIn PDF document text
    • http://kbchina.de/upload/46965526608.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/31464657923.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/fexol.pdfIn PDF document text
    • http://bwlpsalisbury.com/uploads/files/pefobavanivezup.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/71239443518.pdfIn PDF document text
    • http://viettranslators.com/webroot/img/files/16040530360.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/93139550198.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/95248282764.pdfIn PDF document text
    • http://tnslib.su/userfiles/files/mizesasomebomofakoxujul.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/68604245656.pdfIn PDF document text
    • http://usateatop.com/_upload/files/babosaluk.pdfIn PDF document text
    • http://design-klasse.de/ckfinder/userfiles/files/10370093218.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/40198543611.pdfIn PDF document text
    • http://n-production.com/upload/fckeditor/file/36027129920.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/bekiz.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161450c213314d---mebemafofonuludafegilirod.pdfIn PDF document text
    • http://nicolalazzarotto.com/userfiles/files/91769291864.pdfIn PDF document text
    • https://ph789.com/pinhsuan/files/file/sovosijozalizatamodanox.pdfIn PDF document text
    • http://studiovalecchi.it/userfiles/files/78836424542.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16146bb2fee5bb---jerewo.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/bukatujusubofu.pdfIn PDF document text
    • http://himalayakebab.irafbrothers.com/shipinc/userfiles/files/77381994461.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614478b19fe8a---ronofozevirajime.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_off0000c8fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8FD 16800 bytes
SHA-256: 2dd7b5d615dc27cc40c83bbc6e044dd4ed32b5b7abde03bb640cc8966be02472
font_01_sfnt_off0000f423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF423 10532 bytes
SHA-256: 80fc26fa6dc68ec9a2c9fbdcd4d3d5a35dfb6ab094d307963747a81a234c11d9
font_02_sfnt_off00010c5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.