Malicious PDF — malware analysis report

Static analysis result for SHA-256 4872caeac8019443…

MALICIOUS

PDF

76.7 KB Created: 2021-10-10 09:38:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4e47b5b031d192c3bc03b9528258a2d5 SHA-1: 0612f624534a8a6e7b2f34311e2a8f461cec23ed SHA-256: 4872caeac80194431ecdee3ea70f2da0e9482cbcb61a5682f8a05584d1ba49fe
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous external links, many of which point to disposable hosting and are likely part of a link farm. The primary malicious behavior observed is the use of JavaScript to potentially download and execute further payloads, and the redirection to other PDF files hosted on suspicious domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 7

  • 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.
  • 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://drafthe.ru/uplcv?utm_term=crime+lab+technician+requirements PDF link annotation
    • http://wisdomtours.net/upload/file/17939297741.pdfIn PDF document text
    • http://miminku2.com/contents/files/84106045696.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/1398063443.pdfIn PDF document text
    • https://clubslotalmatriche.com/calcas/file/sezubixikidilasofus.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/mn1rjpg1nrq3p79cnle0i4iblb/27697183705.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/74139184330.pdfIn PDF document text
    • https://stijsr.com/userfiles/file/tugigagupimere.pdfIn PDF document text
    • http://delfosventures.net/userfiles/files/3761150738.pdfIn PDF document text
    • https://fibra-optica.ro/ckfinder/userfiles/files/29044148309.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/56223694609.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/mc4b418i8uns339eohbqllls54/14052408675.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/sefufusomuju.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/jamivumiregubokip.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/barajiba.pdfIn PDF document text
    • https://bitree.com/ckfinder/userfiles/files/napazafakijilinafadu.pdfIn PDF document text
    • https://huanghecables.com/d/files/92009202406.pdfIn PDF document text
    • http://templeton.sk/userfiles/file/79467529158.pdfIn PDF document text
    • http://studiotecnicolari.it/userfiles/files/xozonumiwawolewuzolasafos.pdfIn PDF document text
    • https://kitchensofdiablo.com/upload/file/tusiwes.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/lufoge.pdfIn PDF document text
    • http://gibisch.org/files/files/18582791066.pdfIn PDF document text
    • http://vincitydata.com/uploads/ckfinder/files/79361906125.pdfIn PDF document text
    • https://rainbowprinter.com/app/webroot/files/file/zoxibezilogapenunulokuzi.pdfIn PDF document text
    • 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_off0000c837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC837 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE049 17120 bytes
SHA-256: 800174d77fb864adae73c02fee620ca5bf1551b1f1d5e7767d3c03eed040ebc0
font_02_sfnt_off00010c55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C55 10792 bytes
SHA-256: 62124e9632a1dbcc2cba1713ab11fea8f4c203810b3a5076bd444b679083eb30