Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ca4de1d58331bf1…

MALICIOUS

PDF

72.5 KB Created: 2021-09-08 10:27:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6da23f70a2dff0956f6ac216233e8656 SHA-1: cb868fa6b2d3ee195587aa7b351416ddbc4163b5 SHA-256: 6ca4de1d58331bf1582e2067fdd2327d296f8c6a0c0b3c2263ac5ae834c91835
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites. These links likely serve to redirect users to malicious payloads or phishing pages, a common tactic for initial compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/91432ed6853988b5d4f92a60dae629c9/63079239346.pdf In PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160afe3c7d0ada---gunefemo.pdfIn PDF document text
    • https://bushregenerators.com/userfiles/files/44415276735.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7c4f5ab6b---lubanumerivujekulesi.pdfIn PDF document text
    • http://eqletstalk.com/uploads//files/202108111642508960.pdfIn PDF document text
    • https://www.explosivo.gr/wp-content/plugins/super-forms/uploads/php/files/619b3c8b806ff1faa691398df30cda4b/73222607717.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/berekabulugasa.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16085beadb1da9---vunat.pdfIn PDF document text
    • https://www.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160775d7a3676d---73400541413.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3e37caf81---nojumikafajedebepibaned.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160833b51c937c---xobufepowutom.pdfIn PDF document text
    • https://divinenine.net/userfiles/file/bopikub.pdfIn PDF document text
    • https://sanidom.pl/img/file/lexakidirebufobofe.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/20d866e7737b6b94eae6a3c3c102fd0a/63096119503.pdfIn PDF document text
    • https://bodymason.com/user_uploads/files/bifijixala.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac587d494e5---xojobafolasekekiwoxomazu.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/44082944725.pdfIn PDF document text
    • https://alteanetworks.fr/img/file/zavorafogowagoloxora.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606ecaf8c3dec---27869940944.pdfIn PDF document text
    • http://ahknchem.com/upload/files/takuretifiripuri.pdfIn PDF document text
    • http://heureka-cz.eu/files/mewawat.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/bea121bfe3912b0b71096984fdea7d0a/jorigorugosijubozetab.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/65769065768.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/7728028498.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=each+other+or+one+another+worksheetPDF 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_off0000ba2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA2C 10352 bytes
SHA-256: e9a07d04db0e4c6ef93e6c9fb0bc061cb399118a911ec2c0a0768bc757f95e20
font_01_sfnt_off0000d19e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD19E 16688 bytes
SHA-256: 77d5be35a54f2434292b11ae12c27144eac46c1570e145d9e7670248c71a6c43
font_02_sfnt_off0000fc73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1