Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0f2a6bf38cdcd25…

MALICIOUS

PDF

82.1 KB Created: 2021-09-11 12:31:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6c2726ff30a1375abf1837d73874ccb3 SHA-1: 973fea2aad5455a34566378b051c9a5b26b585d1 SHA-256: a0f2a6bf38cdcd256bd7589b2cd2fcb1d2224803256d7d9ba637b74e9d29f653
166 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The heuristic 'SE_BROWSER_INSTALL_LURE' strongly suggests a social engineering tactic to prompt the user to install a fake browser extension or update. While no scripts were directly extracted, the presence of embedded URLs and the nature of the lure imply an attempt to download and execute a secondary payload, potentially leveraging JavaScript for execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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
  • 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 http://www.kigimex.com.vn/ckfinder/userfiles/files/totasefawedeje.pdf In PDF document text
    • http://smolninskayahotel.com/userfiles/file/50544797765.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/jisivasagegopufitedem.pdfIn PDF document text
    • http://haphadoor.com/upload/files/tirazazisev.pdfIn PDF document text
    • http://bursaceyizgelinlik.com/images_upload/files/68512478393.pdfIn PDF document text
    • https://roarmysecurity.ro/mm/file/66068923090.pdfIn PDF document text
    • https://inprovituruguay.com/ckfinder/userfiles/files/bepopimexizesasulifalu.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/9231679670.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161390129d7815---pipodepizam.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/77317298855.pdfIn PDF document text
    • http://sdds.be/userfiles/file/zefesuduxulujetitofupitex.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/tefaxurobo.pdfIn PDF document text
    • https://kocgrafikavukatwebsitesi.demowebsiteleri.com/upload/files/wamamekem.pdfIn PDF document text
    • https://innovativallatgyogyszer.hu/fileok/file/42687901938.pdfIn PDF document text
    • http://nzozkrowodrza.pl/uploads/editor/file/15014430979.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/jokubi.pdfIn PDF document text
    • http://faw-asia.com/image/upload/files/4105370118.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/41134269112.pdfIn PDF document text
    • https://knurussian.kr/DATA/upload/files/202109101459249516.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/venajusafadamedufaxan.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16137c78776474---vexejesa.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/modujupegorogusigoxeror.pdfIn PDF document text
    • https://gornjastubica.hr/files/gufudixujet.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/48175150215.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/finatesogadogakezamekek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+get+real+free+robux+2021PDF 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_off0000dbef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBEF 17656 bytes
SHA-256: d03c83b117edadfb448d5fd248ad14fafff6d51fbc3460894773a124f350bae4
font_01_sfnt_off000109e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109E5 10740 bytes
SHA-256: 089d530a36135bbec4bfb266e03c3527c3a799e9a298a16b88537d02a623c29b
font_02_sfnt_off000122e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1