Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a65880a31fc0834…

MALICIOUS

PDF

84.0 KB Created: 2021-09-02 07:00:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8cff62f0d62eecbda9540866a65522b7 SHA-1: 26ca43c7751580fcfe6e43deaa8c52dee3941387 SHA-256: 5a65880a31fc08349bc82a4227d9041246cc4a988afd85e914956800fea546c7
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. The presence of external URIs and link farms suggests an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://bokaichenyu.com/upload/files/57587539759.pdf In PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f952762522---zinanekupo.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c398831c855---8081659080.pdfIn PDF document text
    • https://ozmutludokum.com/userfiles/file/napukupubilidi.pdfIn PDF document text
    • https://irrisyst.eu/files/file/9664058153.pdfIn PDF document text
    • http://rauvuonsach.net/images/uploads/files/48599872971.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799142655a2---60502354911.pdfIn PDF document text
    • https://airbays.com/userfiles/file/zowadi.pdfIn PDF document text
    • https://fourseasons.events/wp-content/plugins/super-forms/uploads/php/files/34bd7c32493f9ae8bcae2a67fbfdbf8c/40013495443.pdfIn PDF document text
    • http://ettermanenterprises.com/ckfinder/userfiles/files/xigifeweranekumofe.pdfIn PDF document text
    • http://somogyplusz.hu/files/wukulofewoxuwiju.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/1kvgpsu3qkiml7hpg73ukiq9i2/dijojenox.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/96r9mkkk4svt1rdcj9hjpdnom3/13645453764.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/cpcn2bb6thjr972h7dn8vkndp4/78325137161.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b6c1db17d15---30294466044.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b6dead95cd7---xexizakizonadi.pdfIn PDF document text
    • https://giritrademark.com/content_files/files/riwojan.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/gerusadurowotijilijodoz.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/40807785942.pdfIn PDF document text
    • http://rayer.cn/d/files/15440190233.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/45fdb721b7c9180ce90df3234fc50850/fenesurixavagupi.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/temetavagetosufamazomi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=dfd+diagram+in+software+engineeringPDF link annotation
    • http://irodori.kir.jp/files/file/1781014777.pdfIn PDF document text
    • 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_off0000e39f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE39F 17628 bytes
SHA-256: 2beaa44af0f5d21c37d6c36f0604daeab23238fdb9f90f8bdc615ef779f6cc2f
font_01_sfnt_off0001109f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1109F 10740 bytes
SHA-256: 87b617a3dbc3ef79c01e80bfad766839198b8e41b125f5633bd3ca8ec22e6b85
font_02_sfnt_off00012923.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12923 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1