Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7440fb89c1fe8b…

MALICIOUS

PDF

69.3 KB Created: 2021-09-26 01:13:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 924f3a647d927c79115d0f53f89b19c7 SHA-1: bf312d35d82b52010951f2b8b64102600fb1d9bf SHA-256: 8f7440fb89c1fe8b4d0e9438686e79ed00db3ce267284c169f09ff13b90a7fa9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains a large number of embedded links, many pointing to disposable domains, indicating a link farm or phishing lure. The ML classifier also strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crewmak.ru/uplcv?utm_term=where+are+my+files+on+android+phone PDF link annotation
    • http://fk-fudosan.1nino3.com/app/webroot/img/userfiles/files/kenadudagidofozed.pdfIn PDF document text
    • http://antoniolescio.net/userfiles/files/22451982247.pdfIn PDF document text
    • http://thementalhealthadvocates.org/files/userfiles/file/falebepevosavefek.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/mimapi.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/49883350817.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/sewelafa.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/39644525624.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/dozed.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/zereroxapekakosebalovaz.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/68475089165.pdfIn PDF document text
    • http://salsainkonstanz.de/media/files/gizezajujomezuwo.pdfIn PDF document text
    • https://tavcam.com/upload/ckfinder/files/73628969382.pdfIn PDF document text
    • https://ienter.bg/files/21155872988.pdfIn PDF document text
    • http://domplus.su/userfiles/files/mifuxezokikimudibemowuvod.pdfIn PDF document text
    • http://herve-coiffure.ci/files/gasunijij.pdfIn PDF document text
    • http://deleersnijder-bocaege.be/images/file/24627086485.pdfIn PDF document text
    • https://adminico.nl/userfiles/file/63946478593.pdfIn PDF document text
    • http://mesterteto.hu/userfiles/file/45646499455.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/42998512475.pdfIn PDF document text
    • http://mim2010.ru/userfiles/file/pulisodiwomupugum.pdfIn PDF document text
    • http://forestheightsgarden.com/ckupload/files/13053068985.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/wiranitulonadenupilunik.pdfIn PDF document text
    • http://aztkgbv.love-mrt.com/upload/files/53095566983.pdfIn PDF document text
    • https://www.kindspring.org/inc/ckfinder/userfiles/files/10339964012.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_off0000b258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB258 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA6F 10772 bytes
SHA-256: 90156470d2890c42a2191ec5a01279db58d9e88f20f600dfd8f8c86061fb8b6c
font_02_sfnt_off0000e305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE305 14672 bytes
SHA-256: 3838a59fab9b9cbbcbe2a26534ae988a25f0758c91a64629999b3c0597295241