Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac5ffa7666f79a83…

MALICIOUS

PDF

83.2 KB Created: 2021-09-22 11:33:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 37f29b0d2dd6106095e80808abfe60c8 SHA-1: 4ed69d873fa98ec4d70dd6caf63a72fc6f499453 SHA-256: ac5ffa7666f79a838e51d8fed9da2261b174effa06460a927ba8b2fb7b51e26d
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is flagged by ML classifiers and ClamAV as malicious. It also exhibits characteristics of a link farm, with numerous external URIs pointing to other PDF files hosted on potentially disposable domains. The embedded JavaScript likely facilitates the redirection to these external resources, contributing to a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • 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.
  • 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://pearproperties.in/userfiles/file/10370373737.pdf In PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/35129738116.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/31122721845.pdfIn PDF document text
    • http://viacaosaopedro.com/www/js/ckfinder/userfiles/files/gakeronagovawudivil.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/78532196022.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/topegabubijilirazimexiko.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614adfa00ce91---darijejojafakarexizedigal.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139b53f74d67---35644772292.pdfIn PDF document text
    • http://medtravel.pro/images/hand_uploaded/files/jerabinux.pdfIn PDF document text
    • http://rentbucharest.net/images/userfiles/niripofadixufil.pdfIn PDF document text
    • http://illinoislivestock.org/userfiles/file/jedisujomam.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/goxakidovenipat.pdfIn PDF document text
    • http://thevalleytrader.com/files/najuwelonifinaxa.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/39773404515.pdfIn PDF document text
    • https://kingwaterpure.com/ckfinder/userfiles/files/gokalutixu.pdfIn PDF document text
    • http://medeeatour.ro/mm/file/42039902011.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/dipuleripizerakumut.pdfIn PDF document text
    • https://lecormier-menuiserie.com/www/upload/files/poxagos.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/30150942519.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/36005203510.pdfIn PDF document text
    • http://tabouligrill.com/ckfinder/userfiles/files/dobakebebika.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210914090957.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=computer+theme+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_off0000e1c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C6 10680 bytes
SHA-256: 6bdaf26f246b86ca9748ab5ac057f0d70c4db1f1ad9be633b9f60b5405655ef7
font_01_sfnt_off0000fa13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011225.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11225 17464 bytes
SHA-256: 9c5e7e081a4e730427dbb748f4ddd8ab699c398418fb6b19b8213d57f3c0e814