Malicious PDF — malware analysis report

Static analysis result for SHA-256 651883f96d1b13d8…

MALICIOUS

PDF

87.3 KB Created: 2021-08-20 16:55:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 6b1a793b434f9fb7daf43d2e4ab3342f SHA-1: 5c241e1030ada492ed6e5285ecce5a57cdb1a2a8 SHA-256: 651883f96d1b13d85e5f309e7707a04039e1839bd79430281a296ccaf1642f3e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple PDF files hosted on compromised websites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://blsautomation.com/ckfinder/userfiles/files/59385939185.pdf In PDF document text
    • http://lavalnerina.it/userfiles/file/81515659522.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/2qndls0an8tf7p62bf7kq5icts/82857107439.pdfIn PDF document text
    • http://www.buildingmalawi.com/images/uploaded/documents/13608407735.pdfIn PDF document text
    • http://wedding-ideas.ru/ckfinder/userfiles/files/57473086674.pdfIn PDF document text
    • https://yepsell.com/userfiles/files/malakapoferatifutinitigi.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0283a4bc66---31671874911.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/uej72gsue11vnb4bbqgk7bg0h7/mexedopelanigobotomowap.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/82793852223.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202105212024.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090cb3dd0505---32762662489.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210628_03437B25CA18F55C.pdfIn PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/xarofulexelezilukode.pdfIn PDF document text
    • http://benrassam.com/uploads/files/suromezomete.pdfIn PDF document text
    • http://detskaoptika.cz/ckfinder/userfiles/files/puzovibenovudax.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/0e8mhbnngnledp7q66jvu1bj6a/9022019160.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/382bfca50708b28392524cf2e89b8148/6322773341.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d67ff6203d2---mudobosogewafemisedaxa.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/rapivam.pdfIn PDF document text
    • https://aquamedicasatumare.ro/ckfinder/userfiles/files/60594809073.pdfIn PDF document text
    • http://gunjanjain.com/app/webroot/js/uploads/files/ligezokupuvixuzafotisemak.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c05b7261e11---masoxem.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1469ed5f30---zopedomosega.pdfIn PDF document text
    • http://uk-finansist.ru/userfiles/file/ladupubabufe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=breve+hist%C3%B3ria+do+pentecostalismo+brasileiro+freston+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_off0000eb65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB65 11280 bytes
SHA-256: 97a8814fa522eee29c17d75fe55acacf34f190b5bf6b74df4e91d60c06ad6808
font_01_sfnt_off00010541.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10541 18812 bytes
SHA-256: 204f945d5da4c8cbd7d94cdd7e7e53f9a927ee004acfa7fa87cde27837ee2429
font_02_sfnt_off00013321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13321 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1