Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad4f90bb65bde2b1…

MALICIOUS

PDF

77.2 KB Created: 2021-09-09 06:35:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 62ba03e0893b7b9b79c74b4c48ac4db7 SHA-1: a5b8bd3a3f1fe9b7899b85556f8df6bb50c7eda1 SHA-256: ad4f90bb65bde2b131f4145b813848b5a92a3931705dc5900c6f0395e625bff6
174 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it uses a browser extension/update installation lure and presents a download button, common tactics for social engineering. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to malicious sites, likely to download further payloads or steal credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://e-skala.pl/userfiles/file/96082624010.pdf In PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/996104094.pdfIn PDF document text
    • https://el-tall.pl/pics/file/65570914206.pdfIn PDF document text
    • https://psihodesk.ro/ckfinder/userfiles/files/bebomaga.pdfIn PDF document text
    • http://chulatutoracademy.com/chulatutor/ckfinder/userfiles/files/57472620234.pdfIn PDF document text
    • http://vetcasatenovo.it/userfiles/files/xolowokikimerolobizo.pdfIn PDF document text
    • https://jss-moms.si/upload/File/nudedelipizoduposapar.pdfIn PDF document text
    • https://lordoptika.hu/files/files/96982338964.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132c17f916f0---24124296603.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/75353795934.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/67514973456.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/16556348622.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/77929589602.pdfIn PDF document text
    • https://truongthanhco.vn/webroot/img/files/bavuvivetusitewaxisulu.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/kelodizuxebefumupofufep.pdfIn PDF document text
    • http://hrudolf.com/userfiles/jojobifix.pdfIn PDF document text
    • https://sgicorp.com/userfiles/files/99408478735.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/gufunolenap.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/vugotifafato.pdfIn PDF document text
    • http://tryinvest.eu/userfiles/files/xikenufokowa.pdfIn PDF document text
    • http://studiopol.com/userfiles/files/84507268816.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/vatubusogewatet.pdfIn PDF document text
    • https://aslplastic.com/ckfinder/userfiles/files/pegufisunivikanumikusaku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+use+extension+in+chrome+androidPDF 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_off0000cafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE311 10868 bytes
SHA-256: 55a83cdd53741a7ed502058a3c388c7bd47e164ef23f7f9d9b2d96790808d1a3
font_02_sfnt_off0000fc0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC0E 16892 bytes
SHA-256: d4fc7eda5d35595f7341f8b621f34c8ac1540a8745f8b519ab65406fd1d9a417