Malicious PDF — malware analysis report

Static analysis result for SHA-256 d777c821431bc2a3…

MALICIOUS

PDF

104.1 KB Created: 2021-09-18 05:06:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4ec471dac2d505b034852102065f2ccc SHA-1: 18b26fc4697e7d719414e9a97fb5be4013706865 SHA-256: d777c821431bc2a3cc24b8b404f681bea179bdec97ce1c53fa43b6d6fa323e10
134 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains embedded JavaScript and a large number of external URIs, many of which are hosted on disposable domains and appear to be part of a link farm. The primary attack pattern involves directing users to these numerous external links, likely for phishing or to download further malicious content. The embedded JavaScript may be used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142580496340---nofufasigetilomudaveturu.pdf In PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/91706485789.pdfIn PDF document text
    • http://www.rajpuc.pl/pics/file/33276402331.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/guwugifujonanomuxufal.pdfIn PDF document text
    • http://hasyo.net/files/file/69882840598.pdfIn PDF document text
    • http://kovospm.cz/fotky/file/89947001372.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614175b4d7762---wekixofudonatigina.pdfIn PDF document text
    • http://jiin-torng.com/uploadfiles/20210912174645.pdfIn PDF document text
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/76068399047.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/40770808095.pdfIn PDF document text
    • http://tnmetalworks.com/images/files/52675193148.pdfIn PDF document text
    • https://cebrium.ssnn.ro/images/50567022995.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/karudizofexaripuwebe.pdfIn PDF document text
    • https://csam-villepinte.org/uploads/images/file/nazug.pdfIn PDF document text
    • https://pankajplast.com/ckfinder/userfiles/files/39115201578.pdfIn PDF document text
    • http://www.samuitns.com/image/upload/File/tudedipomenuzijonoxi.pdfIn PDF document text
    • http://muzycznescyzoryki.pl/userfiles/file/28338597095.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/98980783207.pdfIn PDF document text
    • https://phukienbep.net/media/files/61729455132.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/wavivu.pdfIn PDF document text
    • https://www.agro-zavod.ru/app/webroot/js/ckfinder/userfiles/files/1750152523.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1630909384.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=minecraft+pe+mods+and+addonsPDF 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_off00012e5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001466f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1466F 19232 bytes
SHA-256: f5d7ee089bcbb86a6d8fade5615adc6aaea828ee484b30d04526d0f309c88cad
font_02_sfnt_off0001788b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1788B 10728 bytes
SHA-256: d37031fa5e27be4c79351ce843503c9e07d2249a72d11479e777cf198edd2256