Malicious PDF — malware analysis report

Static analysis result for SHA-256 332ae3234c68b50f…

MALICIOUS

PDF

86.7 KB Created: 2021-09-11 07:52:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1c72f3ba28a96c7509d4aac0a2e782b8 SHA-1: 111ddf89c498776de3a258a13f7da1d94c93fc84 SHA-256: 332ae3234c68b50fee721df47693a4aeeb093c1502744799f166935b26fdcb1c
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and is flagged by ML classifiers and ClamAV as malicious. Heuristics indicate it uses a browser extension installation lure, a common social-engineering tactic to trick users into downloading malware or revealing credentials. The embedded JavaScript likely facilitates the download and execution of a second-stage payload.

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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 http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/50121420417.pdf In PDF document text
    • http://www.oteliapelsin.ru/ckfinder/userfiles/files/80053486026.pdfIn PDF document text
    • http://edu-soft.ru/site/htmlimages/file/fisepiz.pdfIn PDF document text
    • https://reviewz.eu/app/webroot/files/userfiles/files/jibojujotoxixafotadolepa.pdfIn PDF document text
    • http://olddieselparts.com/ckfinder/userfiles/files/94510803914.pdfIn PDF document text
    • http://tufaghanafc.com/js/ckfinder/userfiles/files/xugagekikiwopivufe.pdfIn PDF document text
    • http://alfatreyd-mebel.ru/archive/images/file/sagutamakij.pdfIn PDF document text
    • https://textosolutionslinguistiques.com/upload/editor/file/72083707281.pdfIn PDF document text
    • https://support-trevianum.nl/userfiles/files/naronugojojotalaxij.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/fabidabetojuj.pdfIn PDF document text
    • https://pracowniatechart.pl/fckpliki/file/25050745165.pdfIn PDF document text
    • https://empezo.xyz/js/ckfinder/userfiles/files/43485828110.pdfIn PDF document text
    • http://vanlysecurity.vn/vanly/album/files/waxedipubaru.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/16527001723.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/13671330495.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/vulopimujut.pdfIn PDF document text
    • http://rainhouse.kr/data/editor/file/376463623612ff42bea3b3.pdfIn PDF document text
    • https://underworldgear.com/admin/images/fckImg/file/60921640014.pdfIn PDF document text
    • https://anjingliar2.com/contents/files/88516965721.pdfIn PDF document text
    • https://empezo.xyz/js/ckfinder/userfiles/files/vudapuji.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/89711836569.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1a2001330---62438070475.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161332c2147c39---fivenu.pdfIn PDF document text
    • http://myepres.com/HotelEstimator/userfiles/file/51618144492.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=uninstall+chrome+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_off0000f02e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF02E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10845 10644 bytes
SHA-256: a27b5bc2b8db92d18f5bdb64604e11de972fe2312ef8bedc3bd9430cfb4d457e
font_02_sfnt_off0001206c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206C 17368 bytes
SHA-256: 923a6cc6cbe9d17186af537c54af803d75ab5e4c5f01943424963345d71a77a3