Malicious PDF — malware analysis report

Static analysis result for SHA-256 95161bdefb257d6a…

MALICIOUS

PDF

99.2 KB Created: 2021-09-09 13:57:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ad5f538efe13b311761d1cfcffa15bf5 SHA-1: f1cbf725d53fd871fc971efb34e0810b899d13c7 SHA-256: 95161bdefb257d6ab10d2e184c2b6fe9d055a522b3a4506486b8bf764dd150e9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://huntic.ru/uplcv?utm_term=curriculum+vitae+odt PDF link annotation
    • https://kvzriu.org/images/file/bages.pdfIn PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/57068878184.pdfIn PDF document text
    • http://alburigiott.it/userfiles/files/18925040968.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/wodebutesema.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffb29525e1---nozujo.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/161379d0d5ddf4---62086218341.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/r8lu13kidbgcuovo70ed6h39ne/4583447128.pdfIn PDF document text
    • http://chroscina.com/userfiles/file/61516285450.pdfIn PDF document text
    • https://avenue102.com/uploads/file/tibuluzaxakete.pdfIn PDF document text
    • https://laser123.com/geektic/files/8089213899.pdfIn PDF document text
    • https://eastmanllc.net/ckfinder/userfiles/files/68049723393.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109050756372504.pdfIn PDF document text
    • https://chineseclothingonline.com/File/mufikiwurevaguduxu.pdfIn PDF document text
    • http://ctmmaximoravenna.com/ckfinder/userfiles/files/208164610.pdfIn PDF document text
    • https://matao.ro/app/webroot/files/userfiles/files/70221418825.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/waraxetomojapu.pdfIn PDF document text
    • http://gsprojekt.eu/userfiles/files/84922185600.pdfIn PDF document text
    • https://angkalaris.com/contents/files/6234909356.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/dafe2319f7bcc916012dd62ae9d2dbf2/60218628259.pdfIn PDF document text
    • https://koratspring.com/upload/file/78407761345.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16139193f0e6f8---16195536037.pdfIn PDF document text
    • http://atomleasing.ru/media/File/nejigegesave.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/72893890278.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_off00012001.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12001 10456 bytes
SHA-256: 15564e630b5b4260190836b9f6ff5461855cb952ad1ac809667caf8becb995ce
font_01_sfnt_off000137ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137CA 18196 bytes
SHA-256: 34118899e2d0f381780630ec4b2346f2021add14b8a45614739d1d9c8b6f1f46
font_02_sfnt_off00016767.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16767 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1