Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f439ba65b203137…

MALICIOUS

PDF

79.5 KB Created: 2021-09-13 08:30:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e92e47987c7d5a1d19907a26f046ac94 SHA-1: 3f9798dd52fb0673fac2814662c7bbf51f725d6f SHA-256: 6f439ba65b203137a4a05d9b095eef41d1ba1473fa6682ae0fa885aa8d47ba64
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning model indicated a high probability of maliciousness. The heuristic 'SE_BROWSER_INSTALL_LURE' strongly suggests the document is designed to trick users into installing malicious software by posing as a necessary browser update or extension. While no scripts were directly extracted, the presence of numerous external URLs, including one pointing to a potential link farm, indicates the document's intent to redirect users to malicious sites for further exploitation or payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://synerhu.ru/uplcv?utm_term=how+to+block+pop+ups+on+chrome+on+android PDF link annotation
    • http://azizolace.cz/images/file/28406484653.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161366f18c07e5---21281929043.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/7425454165.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/gatovaxumumirelu.pdfIn PDF document text
    • http://bharatandcompany.in/ckfinder/userfiles/files/60536494520.pdfIn PDF document text
    • http://www.deep2001.com/images/library/File/gizerajiselol.pdfIn PDF document text
    • https://alemarferries.alemarsnp.gr/ckfinder/userfiles/files/jakojekijorukexozaber.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/74482849615.pdfIn PDF document text
    • http://dyccpharma.com/upload/files/64069538500.pdfIn PDF document text
    • https://osakadentalcare.com/contents/files/lejafevegevez.pdfIn PDF document text
    • https://kochitaxirental.com/ckfinder/userfiles/files/45088648000.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/33510534502.pdfIn PDF document text
    • http://sukhonthip.com/file_media/file_image/file/rifexu.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/wadejoz.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/levemelun.pdfIn PDF document text
    • http://desushibar.com/userfiles/file/60918926041.pdfIn PDF document text
    • http://xn--80aaffebba2apgigwiiececnggk9e4k.xn--p1ai/pict/file/zajimumejesosabavarope.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3a3777e2c---54861303459.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/37991263950.pdfIn PDF document text
    • https://predial-rua-nova.pt/056-CovadaLua/images-editor/file/famagotip.pdfIn PDF document text
    • http://systempro.kr/userData/board/file/86708068345.pdfIn PDF document text
    • https://binarbaid.com/public_html/userfiles/file/42065358790.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/kobagavur.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_off0000d14e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD14E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e960.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE960 17820 bytes
SHA-256: 96421db1892811bd816405aab2eeaa2c6632ed12de2c17e0751338645e4d807b
font_02_sfnt_off000116a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116A6 11188 bytes
SHA-256: 2aaa426c63eda4ba8e84a576a36eda34656a2dc4ab9dcf7df0ae56a5acc52ac2