Malicious PDF — malware analysis report

Static analysis result for SHA-256 9533115ccfaff82f…

MALICIOUS

PDF

81.5 KB Created: 2021-09-16 17:09:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8ff0c75110b007c5364f65236d0c806c SHA-1: 83037abd8790a9e886fadf3b1bd6a0600e35fac2 SHA-256: 9533115ccfaff82f1224944a6f8afb10386c941df15f65d7361114ef240c5416
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and a large number of external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing campaign. The embedded JavaScript is likely used to facilitate the redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 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.
  • 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 http://tuvanluatdanang.com/upload/ck/files/89981407854.pdf In PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/67706976230.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379b0173008---87765219217.pdfIn PDF document text
    • https://northwestconvention.cz/data/files/86088484615.pdfIn PDF document text
    • http://metapolar.hu/tmp/bexije.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/revojove.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/161371afaee9e0---11086477618.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/fobalitekuxogidodozot.pdfIn PDF document text
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/77047870148.pdfIn PDF document text
    • https://bientannamhuy.com/wp-content/uploads/files/27138660351.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/5349433295.pdfIn PDF document text
    • http://ztracenaexistence.cz/files/content/file/7899190507.pdfIn PDF document text
    • http://print-printonline.com/ckfinder/userfiles/files/fujupimizud.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/82180180499.pdfIn PDF document text
    • http://hrudolf.com/userfiles/96193712672.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/makiredesiluwenulejiwusas.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/20198794899.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d1c9ea23dc---bexuwiforaneforifirak.pdfIn PDF document text
    • http://oris-am.com/editor_up/wakelevoxopolapunaziforo.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/pebinomutuz.pdfIn PDF document text
    • http://studiocariola.com/userfiles/files/vodelafejotuledafejefowe.pdfIn PDF document text
    • https://skiclubraonbaccarat.fr/pdf/bopuzegusufi.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109072231127199.pdfIn PDF document text
    • http://battlegrouponline.com/app/webroot/js/ckfinder/userfiles/files/24341529306.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/016fd09593a9bf78430a3ea5870874c1/16774210752.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=good+words+to+use+in+persuasive+writingPDF 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_off0000da38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA38 17264 bytes
SHA-256: cd0d3bff2aa919c1f9617951d868144d03e0e592de3f01d1d5ae9cdb4c6d6000
font_01_sfnt_off000106ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F06 10812 bytes
SHA-256: 47ba2b2aef6dbc8c6c437c64f509fdfd8d42696c1cb9efdbbdd08cd2e5851b90