Malicious PDF — malware analysis report

Static analysis result for SHA-256 41a8df55a479984d…

MALICIOUS

PDF

87.4 KB Created: 2021-06-28 01:13:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 3537ecdf205a4839ff867db6f005b469 SHA-1: 9cd94a0e63c4e9bc73e4a48067f769819d29d222 SHA-256: 41a8df55a479984d4268996d990fa86a39bdcb009d12ca18a98a5c34352076f9
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to websites hosted on compromised WordPress installations, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and embedded URLs are sufficient evidence of the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/773cf2b4379bf7d961105e3bff1ba3dc/90063218374.pdf In PDF document text
    • https://telewebmarketing.com/FCKeditor/file/zexanejo.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/pupupilubupopagojudatofaw.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad9d3e360ef---zilopuwozapedawitejijip.pdfIn PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/r02bkb7h44nue753joe65v3j5h/gapixotudodomoguta.pdfIn PDF document text
    • http://imaginove.eu/data/Files/fodusanomuzavisimetolig.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/c66a44b6e601ace729c9c2dae570e2fa/woturimotujonaxakideku.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/rasudipopi.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a858b08c50d---getemuxijulubiwige.pdfIn PDF document text
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/4850aa6a050fc07668fc40e459a6d5ad/pazobijabigim.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/af9f8dfddb147b6eeb39fb853c279e44/94368097475.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/6q756eo4cgt0a6frl679a0o532/21234297839.pdfIn PDF document text
    • http://www.odnpoznan.pl/fotki/file/file/9263078029.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/pexopuvilexebopavu.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/doruwobowexo.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c5761b9ce42---tozasufaboxopiki.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606da18de7533---darowepot.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f418abad7a---vexojoxuwizovi.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098bd4c6e0f0---41649344066.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aec4059526---38787899528.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-8/20210508204924827275.pdfIn PDF document text
    • https://sinarwaja.com/account/files/vukowofakefidagele.pdfIn PDF document text
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/a1b59e8526f14b8fdb2405ba82e08a2d/rulazolu.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a7e6685990---79425779171.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=strictly+come+dancing+jamiePDF 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_off0000f1be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BE 10864 bytes
SHA-256: 51ee2f32f8ac5751a30d9d6503e1f88b774f3240c23240ee5adba9c094d5e057
font_01_sfnt_off00010a9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000122ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122AD 17644 bytes
SHA-256: b363cd93d192ea3c16f841c8a3a1c17e6a8bb10fb34d2dba908037a6ff94bf44