Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd6f363806139317…

MALICIOUS

PDF

84.6 KB Created: 2021-09-09 06:25:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a74f8efe81a6d8638ce582199cd84d70 SHA-1: ad6273b10138b6d25c8465d34efdbc76082b6e5e SHA-256: bd6f363806139317a1c547ee7a112e1eb2f0c5f6b9cacb89df4b9054f075276f
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicate a pattern of using link farms on potentially compromised or low-reputation sites. The ML classifier strongly flagged this PDF as malicious, suggesting it's designed to redirect users to harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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://nomylo.ru/uplcv?utm_term=future+of+android+app+development PDF link annotation
    • http://pactolous.hu/upload/file/19223616654.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131b2e32803f---82143234329.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/2aef9fb9f1ff62751eee4332f7b0722f/2119595160.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/pugasujizolanofizuder.pdfIn PDF document text
    • https://grancom.by/upload/docs/sozufobuvob.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/kixugitubanijijitanuve.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/4962965184.pdfIn PDF document text
    • http://eubeer.vn/uploads/files/dilabolezoxokivaz.pdfIn PDF document text
    • http://myflora888.com/ck_files/files/kewojuzopuwasexowuzakojo.pdfIn PDF document text
    • http://alexandersorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/20168326647.pdfIn PDF document text
    • http://ameshamagazine.com/js/upload/files/zawuxovalus.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/9456346288.pdfIn PDF document text
    • https://cfacgroup.com/uploads/FCK_files/file/62078315508.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/poravuwuzizitaxelajed.pdfIn PDF document text
    • http://funagamex.vn/PhuongNamGroup/userfiles/files/32626869421.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/43725746466.pdfIn PDF document text
    • http://goodlack.cz/userfiles/file/70535521028.pdfIn PDF document text
    • http://salman-group.com/userfiles/file/guwavose.pdfIn PDF document text
    • https://proartgaleria.hu/files/files/39824110803.pdfIn PDF document text
    • http://jinwoosmc.com/userfiles/file/gewavowanamenifuvemelu.pdfIn PDF document text
    • https://jkmart.net/FCKFiles/File/nusobewef.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-7/20210907002650411120.pdfIn PDF document text
    • http://avon-bratislava.com/files/files/nemodijuvi.pdfIn PDF document text
    • 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_off0000e47e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC95 10632 bytes
SHA-256: c61027b4fa946ddaa04ee885193e0a6bf5fa066c71453c566afd729223c8aec3
font_02_sfnt_off000114d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114D6 18544 bytes
SHA-256: 2e01816d63957e4fdc1c01ebb09f39c88f91aca76e45d59e821b7daefb1deb97