Malicious PDF — malware analysis report

Static analysis result for SHA-256 79c13ff5370ced3d…

MALICIOUS

PDF

82.6 KB Created: 2021-09-16 02:57:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1852ba0036ac8a63c2e9a7a150d2d4e6 SHA-1: 4bab2d9732fea9ce71c21252deda5c97c6e39d04 SHA-256: 79c13ff5370ced3de36290437b173dc3508828be307af16131e52e0d1159ce3b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, indicating a malicious intent to redirect users to potentially harmful sites. The 'SE_CALLBACK_LURE' heuristic strongly suggests a callback phishing or tech-support scam, where the user is prompted to call a phone number. The ML classifier and ClamAV detection further support the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://inwebjor.ru/uplcv?utm_term=naruto+android+games+2021 PDF link annotation
    • https://clubberia.com/js/ckfinder/userfiles/files/34653172042.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/63459750801.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/65646746274.pdfIn PDF document text
    • https://aordonez.com/images/contenidos/files/detoxafapadufavuzov.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/busilovipegosiwozagegufi.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///tujopor.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/35265231731.pdfIn PDF document text
    • http://fese.in/ienupdimages/images/files/20832662514.pdfIn PDF document text
    • https://tlkingatlan.hu/kepek/other/file/dobesivojatoxaze.pdfIn PDF document text
    • http://kurskodkb.ru/page_edit/_samples/userfiles/files/30627538113.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109141437302219.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/bufomudigosejidabaxafusus.pdfIn PDF document text
    • http://matraholding.hu/images/userfiles/files/92268371504.pdfIn PDF document text
    • http://uptindia.com/newsimages/file///semuwaj.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/39486188846.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/livupefol.pdfIn PDF document text
    • http://huthamcauquanggiap.com/upload/files/15570841292.pdfIn PDF document text
    • https://vocembalo.ch/userfiles/file/duvoweferop.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/jejojizasiwe.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d1d28abeb---23846524913.pdfIn PDF document text
    • http://fedime.org/imagenes/67898517061.pdfIn PDF document text
    • http://autohondl.cz/userfiles/file/lezomonovukunejim.pdfIn PDF document text
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/54743637775.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/161309d201dfae---dupejoki.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_off0000df22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF22 10916 bytes
SHA-256: 6eca9292ae1873071ea978cc2914a15ebee0e499dc4ddf4c2c371338dad9545e
font_01_sfnt_off0000f84b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84B 17284 bytes
SHA-256: d2281be53f2a02a7a3d9647e39d994711946ff819c099ee1eda023c1459b6219
font_02_sfnt_off000124bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1