Malicious PDF — malware analysis report

Static analysis result for SHA-256 a163bde345e81905…

MALICIOUS

PDF

83.6 KB Created: 2021-09-08 21:27:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 44102b47faaf7d84ce6df2e954330ff0 SHA-1: 4a63dd8c49ad047b078f6b7219595fe347b4f42c SHA-256: a163bde345e819051ac12bdb24071db2f4a36b0134a6414316e38455b2608d4a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The presence of numerous external URIs, many pointing to disposable hosting and exhibiting link farm characteristics, strongly suggests a phishing or malware distribution scheme. The ClamAV detection and ML classifier further support its malicious nature, likely as a phishing lure.

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://www.mab-solutions.fr/upload/file/23604837151.pdf In PDF document text
    • https://www.santaterezinha.com.br/js/ckfinder/userfiles/files/pusizexunijij.pdfIn PDF document text
    • https://motiwalainstitutes.org/userfiles/file/84172284445.pdfIn PDF document text
    • http://bacvietexpress.com/upload/userfiles/files/27101516079.pdfIn PDF document text
    • http://jogagongu.pl/userfiles/file/lidoxabubu.pdfIn PDF document text
    • http://webbyshoe.com/fckeditor/userfiles/file/vaxakatedave.pdfIn PDF document text
    • http://gardens-spa.com/user_pict/file/41695347.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///golasofu.pdfIn PDF document text
    • https://ibrahimkoc.com/images/Media/files/98758684938.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/71704694219.pdfIn PDF document text
    • https://marbeyoyun.com/calisma2/files/uploads/97053265175.pdfIn PDF document text
    • http://sictombbi.fr/ckfinder/userfiles/files/wevurufidisilejuvase.pdfIn PDF document text
    • http://hotelbasantresidency.com/uploads/41578697286.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/2082a4eac826e40b738fb6f54f18fe31/rolegezukavop.pdfIn PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/83537158628.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/kakapuwudopumobamuxizo.pdfIn PDF document text
    • https://kalimati.in/userfiles/file/33665637613.pdfIn PDF document text
    • https://senarathgroup.lk/assets/media/file/zezom.pdfIn PDF document text
    • http://kdsonline.org/userfiles/file/75623989944.pdfIn PDF document text
    • http://trevelsi.ru/ckfinder/userfiles/files/30170876780.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613687a4cf6b0---26310188796.pdfIn PDF document text
    • http://ceraunavoltapizzeria.it/userfiles/files/71209080922.pdfIn PDF document text
    • http://merlegdoktor.hu/tmp/jiwopegikerolofuki.pdfIn PDF document text
    • https://etest.vn/app/webroot/uploads/files/xugakuro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=parallel+structure+worksheet+docPDF 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_off0000e2c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fadb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFADB 10552 bytes
SHA-256: 022b30fe1db58f6a4893bdf3de191742028509b0a31e539b358d3c936fc61ff5
font_02_sfnt_off00011334.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11334 17556 bytes
SHA-256: efafd545918edaafb55aef7326b3e46c48f7faf304045c4233c2ebe7aead4ed9