Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd5d07858b06c3ef…

MALICIOUS

PDF

81.4 KB Created: 2021-09-13 20:54:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8f9cc4a6803ca5e2bd7b6f3c6f71b9ae SHA-1: d74d3f4de90405a1c1418654ff3a8fa3728ec9cd SHA-256: cd5d07858b06c3efc79bc5c262983ff164dba8705fa2a132c3253482e1d93f41
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to suspicious PDF files on various domains, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, commonly seen in phishing or malware distribution campaigns. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest an intent to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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://vkgnassociates.com/dayafter/uploadimages/newsimages/file/11726511991.pdf In PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/ruxixegi.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613154b458684---wojazasowivimazatarar.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/13656679522.pdfIn PDF document text
    • http://mclarenquartz.in/ci/userfiles/files/22760357156.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/kanadof.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/3421542704.pdfIn PDF document text
    • http://househouse.it/userfiles/files/36769123503.pdfIn PDF document text
    • https://daqing-jewelry.com/uploads/files/202109042018234867.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/zotoralab.pdfIn PDF document text
    • http://e-menu.hu/editor_up/xuposob.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/93685055274.pdfIn PDF document text
    • http://duda-tech.pl/dudatech/upload/file/kuvametok.pdfIn PDF document text
    • http://hongphuc.vn/userfiles/file/rizuwokijuraj.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/fifubizezus.pdfIn PDF document text
    • http://tamphuhiep.com/Images_upload/files/88922492343.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/putetewixudabomajerabeg.pdfIn PDF document text
    • https://bushregenerators.com/userfiles/files/47404510973.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/on6s204e6a4dnvbcbp3e49vlc2/94629536714.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/78660693689.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/12086534781.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/77551795674.pdfIn PDF document text
    • http://sabancilojistik.com/userfiles/file/14469160969.pdfIn PDF document text
    • http://kleiberit.ru/files/file/48290579011.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=vani+meeting+apkPDF 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_off0000d448.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD448 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC5F 10224 bytes
SHA-256: 7eff2c754cf3f30445da640b3101f8f0305b8b9280eb9df48612e2ee1281cbb3
font_02_sfnt_off0001034a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034A 20124 bytes
SHA-256: ee33063646389e2b1a4c36ac665d4f1fde11f8b899fef9f4a56b801fe0f4644f