Malicious PDF — malware analysis report

Static analysis result for SHA-256 d51852c86aa97b2a…

MALICIOUS

PDF

72.1 KB Created: 2021-06-25 21:05:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a47bf3a57d57d64faabe92fd5d13c3f5 SHA-1: 073a6bcd8a90d48901bd8c34cf7694ff82a571af SHA-256: d51852c86aa97b2a0311c8a76b58948cc6bf76de0cbfbb7a39230114b399e4fe
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, directing users to numerous compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of multiple links to WordPress upload directories suggests a pattern of leveraging compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://a2designbg.com/userfiles/file/20996119371.pdf
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/caf282f44dea5bb6cf86a3a9622ecdbb/japuguzi.pdf
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/c8abf8207e05d429479405277f4fda76/zojokepulava.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/4ae580b7569560a170427096fa070d13/49054507718.pdf
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/surlfouv9a92ca6q6thog20skl/23024872332.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093a3615db35---gojesor.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d03f3e6bc---53741386093.pdf
    • http://www.microsinusectomi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e0bb102ac---kadobeso.pdf
    • http://bephoangdung.vn/uploads/ckfinder/files/finuj.pdf
    • http://edwardlankin.com/clients/86087/File/lanoba.pdf
    • http://topspeed4wd.com/ckfinder/userfiles/files/31477826034.pdf
    • http://www.look4job.gr/images/_user_na/file/29433604770.pdf
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a9e99be03a2---62556306623.pdf
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/53c11686c14ebb3a70fc2655f3030306/mugujutesobaribowifu.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/b6534a91b6e180ca1fb64492521b08ac/43861031043.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a90e921adf8---sidimaxedutozi.pdf
    • http://stattus.com/assets/file/nazawemisuj.pdf
    • https://worldmedglobal.com/userfiles/files/24219954600.pdf
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/ebd605828890b39c0bf5e34b71aced0d/sigajozav.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d39245cd2---77144569859.pdf
    • https://anfauglir.com/images/file/kopuvo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=your+computer+network
    • 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_off0000bb31.bin
a93ed0f1c28b338eb63f32c92a06b11654d47b3ba48139d322cd20b15942ac40
pdf-font-stream PDF embedded font (sfnt) at offset 0xBB31 15980 bytes
font_01_sfnt_off0000e45f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE45F 16792 bytes
font_02_sfnt_off0000fc76.bin
af05c51aa1013f0b4d71ba6bf32040181b50348f78fe46f80eea98bbe7528fc7
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC76 10328 bytes