Malicious PDF — malware analysis report

Static analysis result for SHA-256 c927fe0a27ad0d31…

MALICIOUS

PDF

82.3 KB Created: 2021-09-09 02:18:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: eb1a1d2619d855edcb4e8f86c80d126f SHA-1: 2baef26842b7047d57118ff0f549451e2fa89ce3 SHA-256: c927fe0a27ad0d311b12e2d5702b8217897ed9365f4a386820b50136fce96c3b
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, suggesting a link farm or redirection scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicates this is not a legitimate document but rather a mechanism for SEO manipulation or distributing further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://jnvhardoi.org/ckfinder/userfiles/files/963127872.pdf In PDF document text
    • http://francescasciortino.it/userfiles/files/42299949684.pdfIn PDF document text
    • http://focalthai.com/file_media/file_image/file/fukadi.pdfIn PDF document text
    • https://sarenpinler.com/calisma2/files/uploads/relukujagalekox.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613669d27a298---zaxakajowaj.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/29785923848.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/jesitokerepasumeka.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210909060052_yzwtz1.pdfIn PDF document text
    • http://biznesfishki.ru/files/userfiles/files/lemusejujamujegonedizus.pdfIn PDF document text
    • http://yey.uw52.com/upload/files/59763164168.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/xaxikijuruvasipabozavif.pdfIn PDF document text
    • https://pisangmanis.com/contents/files/kabifagexujunubojero.pdfIn PDF document text
    • https://congnghieptauthuyvietnam.vn/upload/files/miwipivivadavitov.pdfIn PDF document text
    • http://blossomtour.net/FileData/ckfinder/files/20210906_92814E6AA2F35366.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/zesabexuvetiborari.pdfIn PDF document text
    • http://principesgs.com/userfiles/file/40792589421.pdfIn PDF document text
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/lowefuximomoniwimol.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/55aab058ab962167a2452d56fe7d09c1/29775006591.pdfIn PDF document text
    • https://hoangphatdanang.com/uploads/image/files/63811724273.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109090703335397.pdfIn PDF document text
    • https://bfull.ru/uploads/files/25700279815.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/5390732190.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+change+emojis+on+messenger+android+2020PDF 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_off0000d7e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000effe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFE 11220 bytes
SHA-256: bcc03d9af9186a50bf9c02815a7de70b6299b054b6b3fd6a4d2247635fd830f7
font_02_sfnt_off000109e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109E9 18932 bytes
SHA-256: bcd310565fe84fd17a4ba2429c5d43a9c0dc5130cd5fb4ac7a507c114a7d30bf