Malicious PDF — malware analysis report

Static analysis result for SHA-256 33cd553b54012958…

MALICIOUS

PDF

83.8 KB Created: 2021-07-23 23:12:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: f78efe8bc2921524fb1097c9419a1eae SHA-1: fc205e4a85438b7b8a15e098991eb81bc3d1d1c5 SHA-256: 33cd553b54012958f4c8eaeadbb1cc8e131a0c2e434c4736fea04d30a1a4f1a7
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites hosting other PDFs. These linked PDFs are likely designed to lure users into downloading further malicious content or engaging in phishing activities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a9aad21e7c---97190782893.pdf In PDF document text
    • http://aucoindeshalles.fr/menu/file/89770343747.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/6cf02cb8b87f74b67be79973836a6702/tifulezesovuwevados.pdfIn PDF document text
    • https://www.swissfillon.com/wp-content/plugins/super-forms/uploads/php/files/5a99d5529be059c63b25476f0027d08a/57898799464.pdfIn PDF document text
    • http://short-story.ru/upload/file/81009219246.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/f4cef33f18d9935c861c2edbb7e86613/jutabafu.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160ee1887eb0d6---5144029209.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/fasafirusevewavago.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/39d7f0bf99e04f11397374b32699bf3f/lufovilofivibuwexu.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/5d8faa11d14d8a4c627076380448e803/gujogexoxujuzimerunoreb.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/3359scitpip5qebdtm4a5sa2mh/tozilulisop.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c089969f5b1---xerosebuwolen.pdfIn PDF document text
    • https://spacio.hk/attachment/file/gugigevokud.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c9305d1af---fakevifukufuzojiworepom.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/iebpmnmoc2p4amnphf65de74h0/98593118018.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096c2ce64e6f---semutul.pdfIn PDF document text
    • http://keigan-productions.com/clients/863431/File/zumab.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/66640520526.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud//files/zidot.pdfIn PDF document text
    • https://elpmarketing.ca/wp-content/plugins/super-forms/uploads/php/files/618e018dd66f0870b2b851e0d065f49d/rusimifagipi.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/4cb8642872f18b0417a82348ea02fb7a/61594355348.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/07afeaec5c05445835d1457e0270ca92/80477848238.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210612001428409281198.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16092310e5f26a---datizufaperibomafezipexa.pdfIn PDF document text
    • http://usa-ex.com/images/blog//file/tebipanedowomomug.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16081b20d660b9---xabijub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=evaluation+mouvement+et+vitesse+6eme+pdfPDF 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_off0000de92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE92 10876 bytes
SHA-256: 13ccff5b0cbe3e327cfa7a81986eb63ac4248f80f03c0ff13a4eab8970d1c48c
font_01_sfnt_off0000f7b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC4 18740 bytes
SHA-256: 02f78e4ad277e08d145d76a2d38eed609c6498d8ae3b3ea3fb93ce2af2c8bdec