Malicious PDF — malware analysis report

Static analysis result for SHA-256 43ff4ab8266da513…

MALICIOUS

PDF

88.2 KB Created: 2021-09-16 00:06:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0719f08542aae4944d95b76888f0aa5a SHA-1: 591562e3ab37cbd357f4f0db8caec8c8b32f15ef SHA-256: 43ff4ab8266da5138275b8ac14954284274620d0d40d97f79fa0e0f256ef2527
142 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external URLs, indicating an attempt to redirect the user to malicious content or download further payloads. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=how+to+make+dark+violet PDF link annotation
    • https://pachetedeturism.ro/images/files/bokugitakanumun.pdfIn PDF document text
    • http://filippodelvita.com/demo/userfiles/file/22803783895.pdfIn PDF document text
    • https://www.cascatai.com.br/ckfinder/userfiles/files/64091926961.pdfIn PDF document text
    • http://didula.com/img/file/39619946103.pdfIn PDF document text
    • http://romangruszecki.com/uploaded/file/metigidedigejud.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/15137194562.pdfIn PDF document text
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/tofoguzibuja.pdfIn PDF document text
    • http://knauto.com/upload/file///vefapiguju.pdfIn PDF document text
    • http://newcityhk.com/userfiles/zadevibozeduxudisu.pdfIn PDF document text
    • http://leise.ru/admin/ckfinder/userfiles/files/79733906090.pdfIn PDF document text
    • http://www.civilhospitalpalampur.in/img/uploads/files/lufagupenikimaduviwit.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/c8a56c14e0d8404fb0c76c0e28cb7bb4/52526272634.pdfIn PDF document text
    • http://stimatacasa.eu/userfiles/files/gogimidukazufuwapipekamot.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/10361568682.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/pemafokuma.pdfIn PDF document text
    • http://jarauwerdaenzn.nl/userfiles/file/dijoxemokupovavede.pdfIn PDF document text
    • http://langmoon.jp/js/upload/files/xifiwixogobokelatixoze.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16138a304543bc---lirojixane.pdfIn PDF document text
    • http://synfarm.com/upload/files/32708185113.pdfIn PDF document text
    • https://cqhuaan.myhost360.cn/upload/files/09-05-14-49-41-73.pdfIn PDF document text
    • http://ux02.wadhost.com/js/ckfinder/userfiles/files/12510833899.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/30795642933.pdfIn PDF document text
    • http://www.miyadenthai.com/image/upload/File/noxegiludevekodubu.pdfIn PDF document text
    • http://veitali.com/upload/files/47470680014.pdfIn PDF document text
    • 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_off0000f0c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C5 10372 bytes
SHA-256: 62db849eee146bb7df0ebe7d44e5cd42db3b4a3edbc4788e019a02fe813848aa
font_01_sfnt_off00010837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10837 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12049 19708 bytes
SHA-256: c84be9263272b375be601af388c62e7b7660fb6aa6f40b35145795baea538166