Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f42479b917c7cc0…

MALICIOUS

PDF

85.9 KB Created: 2021-08-13 08:00:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 934263db8274860d530ec27a078200a1 SHA-1: 6b9ae7c400ccb8bfeb46ab1fc121baabf842dced SHA-256: 1f42479b917c7cc0c06bf4e368f9da9e67e894134a56bfb38c0a7e305028310f
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting. This suggests an intent to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://nexusmediation.nl/files/74758824173.pdf
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/u41tl22rqi1dfe9qmjihulv0t3/nezulasafulepumidebo.pdf
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/86e0a1ffb3d367cb2d20497bb4e02275/relorogupitolevutoxisofof.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160bf629ed5cb0---41345152760.pdf
    • http://weiken-rc.com/upload/files/27438238494.pdf
    • http://reversetheclocknow.com/ckfinder/userfiles/files/dosifanisusagi.pdf
    • http://artgraf24.pl/userfiles/file/womuxewijowir.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/bcue971k80o4duvv04km0l9hi6/28691524756.pdf
    • http://scamps.biz/userfiles/file/gaparufofiso.pdf
    • https://srldirect.com/ckfinder/userfiles/files/10436229438.pdf
    • http://noxsun.com/jingkelun/userfiles/files/20210629135531.pdf
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16078148f27b0d---29588842530.pdf
    • https://rittenhousesmiles.com/wp-content/plugins/super-forms/uploads/php/files/aeb4e219381f20b17b708efea32ac6d7/gajodasupezubezumami.pdf
    • https://joinvita.com/neu/userfiles/file/rowepirokefokujowoziv.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/tui21iu9qimpon1b5mt8balpk2/12450139094.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b34ebd79f0f---61188282350.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071a5529c8e8---11801529623.pdf
    • https://kodcomputers.ro/2664/uploads/weselopimetu.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4de16754d---32680889234.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/897b5739d08ee49ebf5cf55210ecfa31/fenuvotiwaledativujav.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160850fb570e31---66149037244.pdf
    • http://bidmitt.com/img/files/file/18564005593.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=noun+verb+adjective+adverb+list+pdf
    • 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_off0000ea62.bin
92ec4f1684e8067a41ea8d8ad46f5500c2573a5f7b1ee386840e29e0ad5debaf
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA62 11028 bytes
font_01_sfnt_off000103eb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103EB 16792 bytes
font_02_sfnt_off00011bfd.bin
c60c86af8a8a89ce86accad690d70932d64c059e887693513cbb1476fc01a33b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BFD 17596 bytes