Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4e71591903ece00…

MALICIOUS

PDF

83.8 KB Created: 2021-08-07 19:20:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: a3ffbb0fd79f6f83652d77c1159cf228 SHA-1: 49c101eefbd508ebdf75b7587a661dbac6e3edfd SHA-256: d4e71591903ece00b6a6583bba02bf4d21b869d6f0a9d529ce490c9568ddbfa0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or manipulate search engine results. The document body is heavily obfuscated and unreadable, suggesting it is not intended for direct user interaction but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://skywaytravelandholidays.com/ckfinder/userfiles/files/ruzisopidugawezebosigamup.pdf In PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a535b6dab78---leforazabav.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096c55e7a314---8105262261.pdfIn PDF document text
    • http://thecreditcrisis.net/clients/73966/File/50122206726.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/witot.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a14dcab3574---79949607928.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac02ed9151d---94846648028.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bca9091a864---30832387977.pdfIn PDF document text
    • http://bakkervoorwinde.nl/app/webroot/files/ckeditor_files/files/bozilalowobexak.pdfIn PDF document text
    • https://tortugafilms.ca/adminfiles/file/84202143985.pdfIn PDF document text
    • http://eclickapps.in/userfiles/files/nusaguxetin.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3de8b69f4---72191924189.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1606c65b4ccbfb---jipavimejen.pdfIn PDF document text
    • http://robinsonsmithreunion.com/clients/879094/File/tutitomasi.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed2647c4624---vidolinopaponozimujoxo.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/d1f132361c2f366d5fb68c9b67fda440/20463461346.pdfIn PDF document text
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/defa30f901f3522be6a7f1de78bdecc0/lamamiwani.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/63535186164.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/32879623075.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/48605274211.pdfIn PDF document text
    • http://oprfhs70.com/clients/879438/File/78080473022.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/14714336313.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fc63d2058---mapokid.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/kopinawigo.pdfIn PDF document text
    • https://yellowstonewildlife.com/filubulilabobak.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/duzilijo.pdfIn PDF document text
    • https://purefeeling8.com/data/file/24786095437.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=s%C3%A9quence+texte+documentaire+cycle+3PDF 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_off0000df66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f77d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF77D 11228 bytes
SHA-256: 42830494f0181279ea2edcd0d39fe7d848c1a3efa71f715c7fe71c96d1d9a21d
font_02_sfnt_off00011159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11159 18072 bytes
SHA-256: c6046c951bec65ea296111dd14ae80ff00bb6bd27d7fd05bcac6b132760783ef