Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec79caa0459a1431…

MALICIOUS

PDF

84.4 KB Created: 2021-09-10 19:00:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 36bd8d3505ca8a6539c9bacf4956296f SHA-1: d586e3d69b4a359bff0ebed482b05fd0aff056db SHA-256: ec79caa0459a143162b688d42f34c8d60e3f544308639daa165238b5110dbe6b
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm strategy, and ClamAV detection confirms malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, contributing to a phishing or malware distribution attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://perechen-izdaniy.ru/js/ckfinder/userfiles/files/zufegubodedodo.pdf In PDF document text
    • http://grabnerestriche.at/65765990414.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/bezagake.pdfIn PDF document text
    • http://geobigoni.it/userfiles/files/94050806518.pdfIn PDF document text
    • https://wct.goldcrownresort.com/magazine_files/files/pomuxinokikubuki.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/bisenegupijogibubev.pdfIn PDF document text
    • http://abc-tel.ru/data/File/kebamomanepotujidi.pdfIn PDF document text
    • http://costruzionibulagna.it/userfiles/files/mesazi.pdfIn PDF document text
    • http://metabolitplus.ru/files/file/gapifemeviwugevusatekewo.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/xezaduberuvoni.pdfIn PDF document text
    • http://homeopathyhongkong.org/files/xakip.pdfIn PDF document text
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/68118150550.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/40214705981.pdfIn PDF document text
    • https://bloomeng.com/uploads/pivipokubarowu.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/vonudexuvitimimabuk.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/41640095936.pdfIn PDF document text
    • https://threadworx.com/thread/admin/uploads/file/sesitozisuzatunalofam.pdfIn PDF document text
    • http://holidayinntorino.com/userfiles/files/41832983470.pdfIn PDF document text
    • http://youandisagenix.com/ckfinder/userfiles/files/68904905678.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/79666719202.pdfIn PDF document text
    • http://riverside-plaza.com/upload/userfile/files/sufipusimelaso.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613946ab63361---fimodiniliwupok.pdfIn PDF document text
    • http://home-plast.ru/foto/files/65322760263.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/zosatuwodojemagi.pdfIn PDF document text
    • http://videlec.be/ressource/file/44092356361.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=free+cell+phone+spy+apps+for+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_off0000e332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE332 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB49 10708 bytes
SHA-256: 2a961cf91d7846e24014d9772cf03d208ed70db36e8797c63e358ca598956c74
font_02_sfnt_off000113b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113B9 18324 bytes
SHA-256: 9adce730173cd6794f64f2184de2c2cb932682a59578810a80ecd80c537e4667