Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcff9c3451d7b596…

MALICIOUS

PDF

91.9 KB Created: 2021-08-31 05:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: 6d94f7c8011de4ffbed10c97a7d3f054 SHA-1: c32fc9b2c7a36298f155d0b05c30a6e1b254dc95 SHA-256: bcff9c3451d7b596018a4d3680c5f172b9b5db0cff2dbb7c9b7847aa2e5c383d
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to multiple compromised CMS upload directories and disposable hosting sites. The embedded URLs, such as http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608041027e82b---famijesetajero.pdf, are likely used to host or redirect to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/938229813654bb7fa8e55be9e837908c/69924678989.pdf In PDF document text
    • https://tsegypt.com/file/sukafozemirekajariledit.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c86e6b9d6c---fewutudeputilujida.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608041027e82b---famijesetajero.pdfIn PDF document text
    • http://kubabus.cz/novy-web/upload/file/wujuvobetukojeperenola.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/safefukixapafupomido.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/radisexis.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/91450495783.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/femawafakado.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/216d40ee4c96415dc7d43f281b6c8246/mamip.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607031edb08f6---59671382960.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/81baf853e8de1584b2f80086d46f97bd/26050636061.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/78074627195.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/03ts76ltdpuvrbkq90hqvdp161/6174813391.pdfIn PDF document text
    • http://waypl.pl/upload/File/82144049518.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/g89gsphgfd4s9bc2osjllnok3f/92382332557.pdfIn PDF document text
    • http://spad.kr/userData/ebizro_board/file/tevedipizegijetimozabu.pdfIn PDF document text
    • https://gregor-biffiger.ch/userfiles/file/riresifosu.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9dd93af06---72112540552.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae021c9c2e8---jutolowewijar.pdfIn PDF document text
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/49435348330.pdfIn PDF document text
    • http://www.americaninvest.net/upls/files/dagafux.pdfIn PDF document text
    • http://standardamulet.com/files/files/jozodumewumisofimexemuluf.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/81942522285.pdfIn PDF document text
    • https://folklorebridge.eu/uploads/pictures/files/jixemin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=may+the+choirs+of+angels+come+to+greet+you+lyricsPDF 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_off0000fb0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB0F 10988 bytes
SHA-256: c23fe786109ede72b95eeca6ac58bc71cf5ca06ed7180eb8173913306a2eb066
font_01_sfnt_off00011477.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11477 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C89 19944 bytes
SHA-256: 22f5ad80dd5ff78cf2edd6fd750f41febf958a036f51a42d0368018ffbc19a47