Malicious PDF — malware analysis report

Static analysis result for SHA-256 77f634acedc01428…

MALICIOUS

PDF

80.0 KB Created: 2021-09-11 06:45:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bf92287d799e8c7f506f3faed9245eae SHA-1: 86aa0da1e19af380c98efdfc64292ea61f30bcde SHA-256: 77f634acedc01428d74f45d17c0c1f0c2ea78ecb52fa272bd20f61c9291f9571
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many pointing to compromised WordPress sites. This suggests the document's primary purpose is to redirect users to potentially malicious content, such as phishing pages or malware download sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16131175879b27---4763246032.pdf In PDF document text
    • http://lab4050.com/upload/editor/file/kibasowivutaxaxaluru.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a85738baa---1347358408.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/pejubavivi.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/n9prvoqg8qa83ns75i51i72v27/kosufazadux.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c11a783601---53207420745.pdfIn PDF document text
    • https://www.abrasco.org.br/ckfinder/userfiles/files/92537850638.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358f33b7c48---69428779134.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/buridegak.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/gomatugejozi.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161306cbc46810---lumowete.pdfIn PDF document text
    • https://bnovum.hu/downloads/wumowafazilapidubabolavix.pdfIn PDF document text
    • http://rsti.biz/files/fck/file/katojujomutewakok.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/wikopoxemegotokixalaxeke.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/82983869502.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/baa7884edabf0a2bc30bc0d70ab8b093/tonamipivefesituran.pdfIn PDF document text
    • http://bachova-terapia.sk/images/file/38475662189.pdfIn PDF document text
    • http://lambanghieuquangcaogiare.net/vietkiendo/upload/file/dozuver.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/posemetuwotibe.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/vbh0i356tuo97mg1bbhv5r8d24/4923124062.pdfIn PDF document text
    • https://adikketiga.com/contents/files/24291061771.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/73085191522.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612f948104ba4---kotibimonapeped.pdfIn PDF document text
    • http://thesciencenetwork.org/uploads/files/bowuzilasivabadavamoxivef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=atomic+radius+of+biPDF 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_off0000d56e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD56E 10576 bytes
SHA-256: 8d3ec3e7badd56ab3fb43c193334cb8e6f885c14384aa70cfab412ed58c2971e
font_01_sfnt_off0000ed9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9C 17236 bytes
SHA-256: 13ae822842d7700523a28a61309cba8e718d1b6c0bb7a0478fbd6bd2258eccf4
font_02_sfnt_off00011a27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1