Malicious PDF — malware analysis report

Static analysis result for SHA-256 b992da403e819e38…

MALICIOUS

PDF

80.4 KB Created: 2021-09-21 08:10:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 72f8444e5d1a6f876f9c26db8d234ab5 SHA-1: f057b9528737fe307d23c07050c44e9495498510 SHA-256: b992da403e819e388a42a0eab682734822c0e554fd420cc529ba3c1113da33b4
74 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs, many of which point to disposable domains, indicating a link farm. The ML classifier strongly flagged this PDF as malicious, suggesting it's designed to redirect users to potentially harmful content or facilitate SEO poisoning. The presence of embedded JavaScript (T1059.007) is a common technique for exploiting PDF vulnerabilities or initiating malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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://ibtaker.ps/userfiles/file/65052644871.pdf In PDF document text
    • http://tichdiem.surecare.vn/uploads/userfiles/file/letevosubakiwud.pdfIn PDF document text
    • http://paneldeconsos.com/userfiles/file/44433146255.pdfIn PDF document text
    • https://gretajensen.com/ckfinder/userfiles/files/68850000864.pdfIn PDF document text
    • http://diplomat2014.ru/ckfinder/userfiles/files/63619010625.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/xugovipejamidirafexab.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16144bdc9044f7---68104132674.pdfIn PDF document text
    • https://99shayari.in/userfiles/files/24246115260.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/38950423819.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2bcb3ecd1---wajinomalugugiwovipu.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/82241632576.pdfIn PDF document text
    • https://tepatsasaran.com/contents/files/nepelebugekoxuzib.pdfIn PDF document text
    • http://cukiernia.eu/upload/files/tozumibaxavepe.pdfIn PDF document text
    • http://arredamentoambienti.it/img/file/73788033166.pdfIn PDF document text
    • http://dakdekkersindex.nl/images/uploads/beleralewugegakowevegev.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/50820111677.pdfIn PDF document text
    • http://progetec.org/userfiles/files/vofobetopomafuta.pdfIn PDF document text
    • https://purevdavaa.mn/uploads/ckfinder/files/buwapafenulesuwinejegizel.pdfIn PDF document text
    • http://globalbando.com/DATA/upload/files/202109091841267973.pdfIn PDF document text
    • https://brawlcall.com/ckfinder/userfiles/files/10467525774.pdfIn PDF document text
    • https://axlthailand.com/imagexx/files/wevafa.pdfIn PDF document text
    • http://beverly.kopanramen.com/uploads/files/92466737052.pdfIn PDF document text
    • https://clubberia.com/js/ckfinder/userfiles/files/nufasibibiwegazofanozigup.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/43896916474.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=alarm+app+android+githubPDF 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_off0000d775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD775 17368 bytes
SHA-256: ebfad26537fe10310e2611cb54535151f6381f3ad6e4c31d68e3f89d08b15c75
font_01_sfnt_off00010453.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10453 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C6A 10760 bytes
SHA-256: 42b56bc6afb753480f4a3fa4d2d58ad6b2afc210d1ae9f32f7266ffb4c60053f