Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5efad9b79bdc735…

MALICIOUS

PDF

90.2 KB Created: 2021-09-02 05:48:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4e301402c18b8155f141ed87ecc10227 SHA-1: a29be68752e1b269f1e81fa5735224277ea6c809 SHA-256: a5efad9b79bdc735e0c7c8428fad397f0268516dbc0e265dd513a93bfdddd0e8
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple external URIs and link farms on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://stensoproject.com/userfiles/files/sotesijuxasoti.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/ok6fs7qscgoecal6rqje0j43qj/nipijap.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/f98d797ba0a70413186da3c141c2b90a/fixitivaroxatutofasar.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160c9988e55138---83321665721.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e51b20b83bb---tudidipewiv.pdf
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/6pkc21puhnibv9ofol9jh9tjl1/peferalosure.pdf
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/c0b90c499bb02b5c33342d033fa62daa/70471994986.pdf
    • http://bhk-aindling.com/userfiles/files/93385028302.pdf
    • https://bloomeng.com/uploads/nuwopovoxagowosob.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/30176462c3d71f0dd60140df51f9c51c/10643325885.pdf
    • http://omg.su/upload/File/55455544768.pdf
    • http://unicorn-furnitures.com/d/files/zanoziwival.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8dc8410fd5---46210027664.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/4b927c3e5b675298f9954721bb1ba051/19917377894.pdf
    • http://huile-de-nigelle.info/userfiles/file/44775730896.pdf
    • https://chameleoncoupons.com/adgprocessing/uploads/files/16104425187.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608be458570cc---bosunile.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d20364067---buzobukot.pdf
    • http://thunderstar.cn/userfiles/file/20210814032906102778764.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160848c9ad7074---82672527606.pdf
    • https://dm288.rs/slicice/file/72801735085.pdf
    • http://interface-referencement.com/userfiles/file/pepefuxuwotexidomisab.pdf
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/16ddcc0e3ee2ead6683bed612bd9b134/bijogewon.pdf
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/lj2te92gb069511ma3uc8hfo1u/15297748813.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=on+that+note+meaning
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fb4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4C 16792 bytes
font_01_sfnt_off00011363.bin
1e682e7d54ee78a74fd9aa6a8ca145add025c672b8bcaf1b71cc63fdd306a3fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x11363 10268 bytes
font_02_sfnt_off00012a44.bin
1dc53c11a9736ec1d0b67efa9d9937209fcba46eb0c283e77de6e8fdb88dd769
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A44 18988 bytes