Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f385a1c84ac6149…

MALICIOUS

PDF

82.2 KB Created: 2021-09-17 23:33:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 0cac43233739b3002faa8beaa0bf9aca SHA-1: 5537d658f121ef04755724098ae904fef9b70b18 SHA-256: 3f385a1c84ac614972761bc406327d5b4a50f00727c22e5e2ea0a0b02ba5baad
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The 'SE_CLOUD_DOC_LURE' heuristic suggests the document impersonates a cloud service to trick users into clicking embedded links. The numerous extracted URLs, many pointing to PDF files on potentially compromised or disposable domains, reinforce this phishing lure. While no scripts were directly extracted, the PDF structure and embedded links are indicative of a phishing campaign designed to deliver a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • 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.
  • Cloud document impersonation lure medium SE_CLOUD_DOC_LURE
    Document impersonates a cloud file-sharing service such as SharePoint, OneDrive, Google Drive, Dropbox, Box, or Microsoft 365 and asks the user to open, verify, or access a shared document
  • 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://nikunjfoundation.org/ckfinder/userfiles/files/sidemorexameduwodolilize.pdf In PDF document text
    • http://infinity-c-t.com/userfiles/file/belefaxaxarokujusopareg.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/tafukam.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/59288341190.pdfIn PDF document text
    • http://devison-matras.com/upload/file/pafeluzugevugelud.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/69418697952.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/161368205e8ccc---rapozubedonodatebovozumup.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/b0985ba07a02c97ec63c04608008b794/59485782066.pdfIn PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/73075829597.pdfIn PDF document text
    • http://lohoithaiduong.com/uploads/files/94333556601.pdfIn PDF document text
    • http://rulife.ru/ckfinder/userfiles/files/wanurukerivenufebekizege.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/23982086276.pdfIn PDF document text
    • http://gruppocreta.com/userfiles/files/budoj.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/jujidesubipeset.pdfIn PDF document text
    • http://sterenstein.ru/userfiles/file/muvix.pdfIn PDF document text
    • http://cukrarnakolbaba.eu/obrazky/files/mevijenadaxidofo.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/lozogigidobijonavaxowe.pdfIn PDF document text
    • http://3wsystems.com/shipinc/userfiles/files/94744866451.pdfIn PDF document text
    • https://fresh-cherries.com/ckfinder/userfiles/files/sadez.pdfIn PDF document text
    • http://shrlie.com/upload_fck/file/2021-9-9/20210909092423328419.pdfIn PDF document text
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/wuzajuzulugu.pdfIn PDF document text
    • http://tartak-monis.pl/tartak/images/file/domam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=delete+trash+folder+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_off0000decc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDECC 10452 bytes
SHA-256: b17f467ac22b8a4ef8dae590a158c2cfb95bb47ecd602ecb6fe8daa26f9cfe8d
font_01_sfnt_off0000f671.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF671 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E83 17244 bytes
SHA-256: 5c323659dcf885167a514c995a378a0600da627deaab5eb67d522575a9207317