Malicious PDF — malware analysis report

Static analysis result for SHA-256 99f83128ca5bf3d8…

MALICIOUS

PDF

74.8 KB Created: 2021-09-13 15:34:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: abca9df68da0da166409b7b83d841c92 SHA-1: 755104f219566c7d0e87a08b6b95c4b750ea368c SHA-256: 99f83128ca5bf3d891912bd0fa5d37287d1b88b3ca2288f0d243954918f50c18
150 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The ML classifier and ClamAV detection strongly indicate malicious intent. The JavaScript likely redirects the user to one of the numerous external URIs found in the document, which are often used for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 8

  • 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.
  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.
  • 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://sichera.eu/userfiles/files/lebebadipevipojudebijewa.pdf In PDF document text
    • http://www.amedna.com/userfiles/files/82947589672.pdfIn PDF document text
    • http://bubb.cn/up_file/file/8356783559.pdfIn PDF document text
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/tovefenudevaxubika.pdfIn PDF document text
    • https://flyags.com/editorResources/file///waxapupepidusegamasegobes.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/62561396399.pdfIn PDF document text
    • http://vlajkylevne.cz/UserFiles/File/8138389125.pdfIn PDF document text
    • http://jeansresource.com/js/ckfinder/userfiles/files/suwebuborufigojajozu.pdfIn PDF document text
    • https://ecoolteh.eu/galeria/file/wadojukanokob.pdfIn PDF document text
    • https://vroa.pl/chplusfiles/file/34324859884.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/9lsna99dv1geu387fct5ltpn27/57483860357.pdfIn PDF document text
    • https://johanbjerke.se/userfiles/file/96177811580.pdfIn PDF document text
    • https://flims.atelierleuthold.ch/userfiles/files/94561675705.pdfIn PDF document text
    • http://fundacjaproartis.pl/javascript/ckfinder/userfiles/files/80809623377.pdfIn PDF document text
    • https://bevillelecomte.ovh/ckfinder/userfiles/files/84316318828.pdfIn PDF document text
    • http://langmoon.jp/js/upload/files/tewoted.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/161364c02e96c5---ligine.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/kekalofigodejiwufexexiw.pdfIn PDF document text
    • http://pecsimutargygaleria.hu/files/file/leninakoxaxubaxufere.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/tovevo.pdfIn PDF document text
    • https://etevent.itweald.com/uploads/files/613677a0cd5ce.pdfIn PDF document text
    • http://dsacare.com/admin/uploads/file/naxibijakugetolikabute.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=download+uc+mini+versi+10PDF 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_off0000c13e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC13E 16940 bytes
SHA-256: 4e109694fa38d2c1b8002c68ec4d6e29f2cb98e3e7f228adfb9226e2e892b39a
font_01_sfnt_off0000eceb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10502 10860 bytes
SHA-256: 5c71f5ed8f7ab0deb8fdb25e1baf35580b7d79f2331a538beef952ac40e0937b