Malicious PDF — malware analysis report

Static analysis result for SHA-256 e2436ce794830313…

MALICIOUS

PDF

86.3 KB Created: 2021-09-10 16:52:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4b19f159ea2dff533696f063adc4255c SHA-1: 2f9729447e609436f9ba68035d6c8c09a1523964 SHA-256: e2436ce7948303135a79892eb32ef27b0fd1537a7b73ba742ccfb4beee6f4911
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which point to disposable domains and appear to be part of a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://kimcert.net/E/file/mebem.pdf In PDF document text
    • https://helices-evra.com/userfiles/file/99887260943.pdfIn PDF document text
    • http://www.satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/18194134374.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/63684354702.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613164b8d3d28---mixelovusamazuzowup.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1612edd2615f46---batamabepufejofi.pdfIn PDF document text
    • http://keacg.com/upload/files/pekoxakigumagejutexewilo.pdfIn PDF document text
    • https://apskarota.org/userfiles/file/kogimajoj.pdfIn PDF document text
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/xegeduj.pdfIn PDF document text
    • http://talani.nl/userfiles/image/file/mukimur.pdfIn PDF document text
    • http://leise.ru/admin/ckfinder/userfiles/files/26368882955.pdfIn PDF document text
    • http://beccaro.it/userfiles/files/gufetipobi.pdfIn PDF document text
    • http://www.enredmail.com/templates/files/idCliente_/file/fabaduwekopovuxi.pdfIn PDF document text
    • https://www.lire-les-notes.com/ckfinder/userfiles/files/goxagepamobadowolulabixes.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/61541759099.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/fuvozumapuwexobemitesilud.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/volilotutod.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210902191043.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/fuketumo.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/66481770706.pdfIn PDF document text
    • https://markiza-trade.ru/admin/ckfinder/userfiles/files/tozetoxivenolujadujixof.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/42903305378.pdfIn PDF document text
    • http://juha.be/_files/file/69697270592.pdfIn PDF document text
    • http://mengnuanua.com/app/webroot/files/files/13900752051.pdfIn PDF document text
    • http://forglory.cz/ckfinder/userfiles/files/fomimovamoxegaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=drawing+apps+for+android+like+procreatePDF 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_off0000eb11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB11 10972 bytes
SHA-256: 868f9ad17639259d60af11c76a3ff9a2364d1f3b61c3d5578c1df9cee9ab4b22
font_01_sfnt_off00010483.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10483 18200 bytes
SHA-256: fa4f3fd53521d4d67cdc35b3f39c9805643f67a891fb6ada65eb8734d0d7b67d
font_02_sfnt_off0001333c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1333C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1