Malicious PDF — malware analysis report

Static analysis result for SHA-256 80880722c0dc22d9…

MALICIOUS

PDF

72.0 KB Created: 2021-07-02 12:22:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2822760cae5375a17b09bff964aef6dc SHA-1: 259f66fe2e000409922f6ccac4616bc0e691fe17 SHA-256: 80880722c0dc22d9667307fe97576e407d99e4e800185c49db7c511d084b00f6
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other domains, indicating it functions as a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but serving as a vessel for the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://catamma.ru/uplcv?utm_term=instrument+used+to+measure+turbidity+of+water
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3c1445474---zaruwepijefoworiba.pdf
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/98b9ace0f30aa9096887cff2a26b2d66/fojet.pdf
    • https://mebelihome.ru/upload_picture/nawibomod.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b324374fc---zibobowexo.pdf
    • http://harchovyk.com/userfiles/file/wavuzajudolike.pdf
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/f06564c5dfc6df2469da65ea52b0d584/61830400263.pdf
    • http://akcjonariusz.com/UserFiles/file/ligutewer.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/0ac23ae83ff9411ae3f133212d4bca15/27744652358.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a490653a6ed---lasopag.pdf
    • http://sklepjola.pl/userfiles/file/towerawabe.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/kleab2phg36hntjbjh9691kskt/gunegogojaxekazaw.pdf
    • http://sunnysolutions.it/uploads/assets/file/28027300113.pdf
    • http://szao-spb.ru/images/news/file/80120598151.pdf
    • http://orourkelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/89411316285.pdf
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/770e9003a9b4090066280ad2fa59682e/57861289291.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/20togaou6aok0fqmapk64tmvo2/kenizovonego.pdf
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/ed25374ec224a3b07e00e5581472398b/62559006363.pdf
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/fokijerarekevawuxewemeto.pdf
    • http://glotecgh.com/upload/editor/file/93234079733.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b889c8b97c6---40289265293.pdf
    • http://x-site.by/upload/editor/files/51302035253.pdf
    • http://hoanggiaphatland.com/uploads/image/files/63892963256.pdf
    • http://www.aluvascientific.com/UserFiles/file/54961908048.pdf
    • http://zlato-invest.cz/upload/files/viserigojatux.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_off0000b718.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB718 16792 bytes
font_01_sfnt_off0000cf2a.bin
1987c6127ff81c6f92bb54e08c78bc8fd875e5ad0d966e8ff4dde66a53f1ecf4
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2A 16528 bytes
font_02_sfnt_off0000f93d.bin
559cfa94e60adf0963ce0e9f6b461d6d0b879a127b9c1c1a2ddd87186241a7ba
pdf-font-stream PDF embedded font (sfnt) at offset 0xF93D 10860 bytes