Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb21e8c223db430f…

MALICIOUS

PDF

100.6 KB Created: 2021-09-03 00:48:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6407b6127349ddfa32ded2b98847ad80 SHA-1: f4131e25dae380828f571653b7e0c942b0794b1a SHA-256: bb21e8c223db430f8c5791171a228163aeda2c26a7b7e827d0bd83107c8bc005
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm with numerous external URLs, many hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The structure suggests a deliberate attempt to obscure the malicious destination through a large number of redirecting links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://serting.eu/userfiles/files/72254921707.pdf In PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/e48e133a6a34c4a9cda5f16d16f46023/zabosalifit.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/82156644219.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/gixezarin.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/nomegitewozaladujavuruma.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b1d73a13fa4---luraji.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/82548077185.pdfIn PDF document text
    • http://northphoenixmustangs66.com/clients/4/4b/4b49b54eec06ebba3741256e9f3e6f2b/File/jumodenotemabegape.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/28hf6ia01cn00d28it70clgnrv/65334834814.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/20df7167782a7a20e21398a16a014df2/mababunub.pdfIn PDF document text
    • https://ratosatu.com/contents/files/38774448646.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/22a978a12c6d0f4cb2cbc54a5343c942/bumitowijagixaxuzobo.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/6152099539.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/jewasig.pdfIn PDF document text
    • http://kuresi-kaitori.com/upload/content_pic/files/19512360137.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/35490684946.pdfIn PDF document text
    • http://debden.org/userfiles/file/99673529632.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/69305175508.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/l2ls520s019nn7n448c41ts85s/pikuzibuj.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/33281a746a091c788260284f8d06e647/50169809343.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/wijija.pdfIn PDF document text
    • https://konteshamamotu.com/userfiles/file/46533440735.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a047a4653d0---73810317840.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/0k7b9hiq9csnlvn7p0sbj1ale5/bezerupetexe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=mega+liste+d%27aujourd%27hui+pdfPDF 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_off00011d34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D34 21132 bytes
SHA-256: 5a2f7db9bb7b656020d8ad4beb1cc1b86ff9c751f9d1ca3e20424cde93fd618b
font_01_sfnt_off000152dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x152DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016af3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16AF3 10928 bytes
SHA-256: 1d51cda8833b2fbef9bbf5de22d6d5ca980c32a91f4270c80ea8086da791d6dd