Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4f3a8d0f7e80923…

MALICIOUS

PDF

79.8 KB Created: 2021-09-09 10:51:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 517f88738eab4bc44caf900043ec0578 SHA-1: 13ed1ebf5f23df461db25a26a8ddc0ca7e3837c3 SHA-256: f4f3a8d0f7e809234e89965ee541ca0cca7646f0e4b4ff8d14739c146411f529
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document containing embedded JavaScript, which is a common technique for delivering malicious payloads. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects the user to one of the numerous external URLs, which are often used for phishing or to download further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests a large number of links to disposable domains, further supporting a malicious distribution or phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 https://drafthe.ru/uplcv?utm_term=game+sadis+di+android PDF link annotation
    • https://xeroxexpres.cz/userfiles/file/javiwulobisexadidaned.pdfIn PDF document text
    • https://traiteur-troyes-mariage-buffet-aube-10.blaisot-traiteur.fr/ckfinder/userfiles/files/zosodemaj.pdfIn PDF document text
    • http://gibisch.org/files/files/pomuzosonanetiselawi.pdfIn PDF document text
    • http://slesnick.net/userfiles/files/dazafupexidogu.pdfIn PDF document text
    • http://omegapizza.net/uploads/files/9958054780.pdfIn PDF document text
    • https://indobaliart.com/sitefiles/file/ganixatedajefur.pdfIn PDF document text
    • http://tlumacz-lipno.pl/pdrzewiecki/files/20890997632.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/bixerogapo.pdfIn PDF document text
    • http://pozitron-s.ru/userfiles/file/fuwafuliguvevagi.pdfIn PDF document text
    • http://nwatchonline.info/userfiles/file/dugadawofesosom.pdfIn PDF document text
    • https://dragonexpressml.com/userfiles/files/15932749048.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/moxopezama.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/c9ad3bc9a6dd3f5a9e7f625c14be1481/mekalezugu.pdfIn PDF document text
    • https://perfectsextherapy.com/public_html/userfiles/file/jejerusobo.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131842b63a25---94787890831.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/zetirotupozozomokoz.pdfIn PDF document text
    • http://epodhajska.eu/UserFiles/File/66787278975.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/86109449047.pdfIn PDF document text
    • https://njshore.drinkpoint.com/uploads/files/xowiwoginixetegurazupo.pdfIn PDF document text
    • http://desiaussies.com/ckeditor/uploads/files/25796550888.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/wexejuga.pdfIn PDF document text
    • https://ddnepal.com/assets/userfiles/files/35284479715.pdfIn PDF document text
    • http://teen.plovdivweek.com/js/ckfinder/userfiles/files/67376552864.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/39986360098.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/65402488158.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_off0000d5cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5CD 17184 bytes
SHA-256: 374b0f73dbec928ba759184906a3c6dee7de30d8482eb5e5cda14de38367809c
font_01_sfnt_off0001022b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A42 10304 bytes
SHA-256: 794cb5635d3924538a292289f00f8f1740281ede3dc297e8f4c259defdba4313