Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e16387761159139…

MALICIOUS

PDF

80.6 KB Created: 2021-09-09 04:51:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8fdfa10dcc649eb60ce4982575b24384 SHA-1: 4665d1bdf546a6a2f570a211c13acf8df637c6a5 SHA-256: 5e16387761159139960fead4db3a433a2fd6148787929d7f680944aad6acd8b8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains and are indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is a common method for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://csom.cz/wp-content/plugins/super-forms/uploads/php/files/032bb6022462e5e3347638091f70432c/62737418742.pdf In PDF document text
    • http://cichanski.com/Upload/file/ruxazat.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/161330caed5e37---99351868281.pdfIn PDF document text
    • https://kaptenhoki.org/contents/files/31618278853.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/98935640809.pdfIn PDF document text
    • http://wernersuarez.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13412822478.pdfIn PDF document text
    • http://vigen12.com/userfiles/file/netarivemi.pdfIn PDF document text
    • https://airxps.com/userfiles/files/duwamovir.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/78401411361.pdfIn PDF document text
    • http://peach2560.xyz/js/ckfinder/userfiles/files/62201097413.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210901143559.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/sawamisib.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/44747761957.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/62529746825.pdfIn PDF document text
    • http://kleinschadenexperte.de/userfiles/file/43137187256.pdfIn PDF document text
    • http://thesecurityguardunion.ca/userfiles/files/guwasedevoki.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/fipadulufaw.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/63074939352.pdfIn PDF document text
    • http://alfadent-volg.ru/images_uploads/files/zikanifenigetadevav.pdfIn PDF document text
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/figiraforafaromite.pdfIn PDF document text
    • https://centrumschoolka.pl/photos/file/68881057246.pdfIn PDF document text
    • http://ck-buhgalter.ru/userfiles/file/sexowedi.pdfIn PDF document text
    • http://coffee33.ru/archive/file/xedugirilewizo.pdfIn PDF document text
    • http://msdoubrava.cz/foto/images/file/gaselutezep.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/98656079870.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=teamspeak+3+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_off0000d76b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD76B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF7D 17480 bytes
SHA-256: 37912801042deb4c1d533c50600eb149f75131ef83b35c4183b47a5e276006c7
font_02_sfnt_off00011c85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C85 10744 bytes
SHA-256: 4ee887d64a71e53fc973af2ab2194489748cf12eb68148d69841beee04410cab