Malicious PDF — malware analysis report

Static analysis result for SHA-256 21bf644d2384fc05…

MALICIOUS

PDF

69.8 KB Created: 2021-09-28 19:32:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: eafaa4f75cb95d9377cb4d0fa1bc7f1f SHA-1: 31488c77da522935f67b75db3610a747a05297bc SHA-256: 21bf644d2384fc0529beb39390f515fb1dc2eb8285123a954564b271269f84ba
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many of which point to disposable domains and form a link farm, suggesting a phishing or scam lure. The PDF's structure and the presence of these links strongly indicate it's used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://queure.ru/uplcv?utm_term=genshin+impact+may+2021+codes PDF link annotation
    • http://cmtoolsrental.com/user_img/files/78999437922.pdfIn PDF document text
    • https://www.sacict.or.th/ckfinder/userfiles/files/kojuwosutepumujurad.pdfIn PDF document text
    • http://kingsfci.com/userfiles/file/21184977381.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/25142001519.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/pedejel.pdfIn PDF document text
    • http://gddfboiler.com/uploads/files/25142439864.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/defokijem.pdfIn PDF document text
    • http://boldino-hotel.com/ckfinder/userfiles/files/lebot.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/11714860553.pdfIn PDF document text
    • http://epicridesnepal.com/files/61898409339.pdfIn PDF document text
    • http://sinhorelli.com/userfiles/file/wiwazarukozixado.pdfIn PDF document text
    • http://ruihuitax.com/files/file/3097226839.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16136e29f1e768---2228178183.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/44831522346.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/tizudipusasigafumukiza.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/95503904186.pdfIn PDF document text
    • https://strings97.hu/userfiles/file/7161617045.pdfIn PDF document text
    • https://abhimaninteriors.com/ckfinder/userfiles/files/sapinu.pdfIn PDF document text
    • http://cocoal.com/uploads/file/9502865306.pdfIn PDF document text
    • https://maribon.net/app/webroot/files/userfiles/files/rilubom.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/39668717801.pdfIn PDF document text
    • http://studiotecnicodavico.eu/userfiles/files/sokusexufi.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/lelutalixefugolesiro.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/zoxowosajuwogepegiwu.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_off0000b1d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1D3 11080 bytes
SHA-256: 9f82952037017132dbf247a2ea19122720b4324c1aedae2d03fc510f7376fd98
font_01_sfnt_off0000cb9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB9D 15016 bytes
SHA-256: fbd513c39728de55ec368aba59256df7f83e739abef7c2643b221fb23ca9a13e
font_02_sfnt_off0000f15d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1