Malicious PDF — malware analysis report

Static analysis result for SHA-256 091697548d786885…

MALICIOUS

PDF

83.1 KB Created: 2021-09-09 16:19:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 14bb945b78eb90369b1db2dc82fc2f92 SHA-1: 91985933cda3a38c789cd90f2c2aa429f69ce7d0 SHA-256: 091697548d786885b79f4eeb4b123c74d42e9d90948f04fa8a99d56a4172d1db
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It functions as a link farm, containing numerous embedded URLs pointing to other PDF files hosted on various domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high volume of links to distinct, potentially disposable hosts, suggesting a tactic to manipulate search engine results or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • 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.
  • 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://ristorantebiscione.com/userfiles/files/wuwevekojivot.pdf In PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/tuwelixuvogadotu.pdfIn PDF document text
    • http://camdohungdung.com/upload/files/53980034191.pdfIn PDF document text
    • https://phukienbep.net/media/files/20014344157.pdfIn PDF document text
    • https://bangvetthuong.com/luutru/files/38009998257.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/papusemok.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/584d9122f9fe80f7222374c12cf7b643/47821093206.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/jezugovepususovisalileli.pdfIn PDF document text
    • http://sieuthibds.net/images/files/59035525381.pdfIn PDF document text
    • http://leicesterbiketec.com/userfiles/file/deberuvosujanurivi.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/36348996567.pdfIn PDF document text
    • http://cegled.varosom.hu/userfiles/files/76827335638.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/51946628922.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/82192013298.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/93819982356.pdfIn PDF document text
    • https://willmarareachamber.com/ckfinder/userfiles/files/kemiwisavovowox.pdfIn PDF document text
    • https://yifff.se/userfiles/file/jusadunobirow.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/17046198726130b549c36cc.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133dd0c8d7c8---wapabigetikilavakixedi.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/wamafamonodovikeme.pdfIn PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/jegadexolepamafefa.pdfIn PDF document text
    • http://free-note.kr/files/fckeditor/file/856160131613878b5d3d5c.pdfIn PDF document text
    • http://hai-bi.com/uploads/files/202109080753358804.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/32275068257.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/xebasugitifupadalunag.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/57718393800.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=battle+of+memories+watch+onlinePDF 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_off0000ddfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDFE 10740 bytes
SHA-256: 0fbb43d5b4447032c3f5788c573644a01f22b6f5f1c9a5b9d9cd5e35cefc87ef
font_01_sfnt_off0000f695.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF695 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ea7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA7 18260 bytes
SHA-256: 677b939548cf8bd6db1c4ea48560009c50f93b7eca0196fec62f8a5ad4b55fe3