Malicious PDF — malware analysis report

Static analysis result for SHA-256 de9741550aab5448…

MALICIOUS

PDF

85.6 KB Created: 2021-08-30 11:55:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 957e2bad36d2873ed77a9692a2dcc929 SHA-1: 084a2066cf7cca30e682057f621c8f73ec729c49 SHA-256: de9741550aab54485872df8d0432c819ed858b2442ade101b7bbc83ed16e41ac
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It contains a link farm hosted on multiple compromised websites, suggesting an attempt to obscure the ultimate destination and evade detection. The presence of numerous external URIs and link farm heuristics points towards a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086950acf671---42238276081.pdf In PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/7a941b48e7e061b88196018a4ae70abd/10480398512.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3e1648ded---vivufemineroneninovo.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/hj8h3vc9vjk1mo99e8nskj0636/ligitutagaraj.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e0b7eb981a0---30857945943.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99978362211.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/40527102627.pdfIn PDF document text
    • http://fotobambagiotti.it/userfiles/files/41207098044.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/rulitojugimidive.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb4c727276---minosizadeko.pdfIn PDF document text
    • https://fong-cai.com/upload/files/fixasakesiwopijik.pdfIn PDF document text
    • http://hiroshima-teishaku.com/userfiles/file/sasazegoz.pdfIn PDF document text
    • http://vansuloi.com/uploads/userfiles/file/61743295478.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/17321738682.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-7-26/20210726023810925786.pdfIn PDF document text
    • https://wic-net.com/userfiles/file/25872984920.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a79835b0d5b---18613460845.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ee265691e6d---soxixunikapufokokenige.pdfIn PDF document text
    • http://zatexpress.com//upload/userfiles/files/penamom.pdfIn PDF document text
    • https://encoregallery.us/wp-content/plugins/super-forms/uploads/php/files/7626441e5d087d47be7a1e98398dc503/juzapuwadilarumuje.pdfIn PDF document text
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/62237090355.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3a2858444---donowefogelawar.pdfIn PDF document text
    • http://hifimarkt.eu/kunden/kronhardt/ckfinder/userfiles/files/34052412069.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a64d7c0c60b---37644868914.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+reduce+file+size+in+indesignPDF 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_off0000ea2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA2D 17804 bytes
SHA-256: 528db1a8b7d1d076d0664e801d9b44bd8bfe9f32df13078e223069ca03cab747
font_01_sfnt_off0001182c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1182C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013043.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13043 10728 bytes
SHA-256: c8a3e64532924e6f2607c7491d2d49650d709cc8dc61bcd6adab2d183f3b06a8