Malicious PDF — malware analysis report

Static analysis result for SHA-256 f39d6ca1545abd30…

MALICIOUS

PDF

77.7 KB Created: 2021-09-22 23:43:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 0660d7d9504f425c94e36a199266a882 SHA-1: 44b015c091a3080cc98cd1859eafe91844a4ceb1 SHA-256: f39d6ca1545abd305e0aca1f65c2370a1600058340463184e8f2ac8ffa8e0f43
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to disposable hosting, characteristic of phishing or malware distribution campaigns. The presence of external URIs and link farm heuristics further supports this assessment, suggesting the PDF acts as a lure to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://irlanc.ru/uplcv?utm_term=no+application+can+perform+this+action+android PDF link annotation
    • http://sahrugs.com/userfiles/file/23479435816.pdfIn PDF document text
    • http://seghers.kr/data/editor/file/181125053661353a715bf17.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/48416914901.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/76066988453.pdfIn PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/zujuruvizawuvoxanakiwok.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/nufugofubelerufodugog.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/zibasijexutiw.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/5b69d4a0822e755b18b15eb23a7c0c59/muwurofedemutikejize.pdfIn PDF document text
    • http://giaodantanthaison.com/Images_upload/files/67976035427.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/pesuwugogifavozif.pdfIn PDF document text
    • http://cukrarska-vyroba.cz/UserFiles/File/zizitufemozovadiwen.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/62997848219.pdfIn PDF document text
    • http://svx.su/ffile/file/2478621566.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/75573181212.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/17235789829.pdfIn PDF document text
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9973272025.pdfIn PDF document text
    • https://sin-wa.tw/app/webroot/userfiles/files/zarukaxubilosurosutuvunej.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/7803170892.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/limap.pdfIn PDF document text
    • http://test-immo.com/file/lunebad.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/mizorugi.pdfIn PDF document text
    • http://savalis.ru/userfiles/file/zenagikotenatifaferuxo.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_off0000c1eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1EB 20864 bytes
SHA-256: a3dfa06e1dca44ed195ee578cd8e2588438aadfd9fabaaaaa4eb687b2650da18
font_01_sfnt_off0000f799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF799 10864 bytes
SHA-256: 6d2ba99531046e0a9c9b933c96a565b82b9b7f47c58ed703c54c84687049ec3f
font_02_sfnt_off00011088.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11088 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1