Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c76adfe548eabd6…

MALICIOUS

PDF

110.6 KB Created: 2021-06-28 00:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 8f28db417fcd133bca8d5d614f3c1ad6 SHA-1: 6e135818e325254d0e5a3b27e619ec3e684f5721 SHA-256: 4c76adfe548eabd67f8734f3b84e9d96d5ca84501295b37a546222c69263eba0
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress installations, suggesting it's designed to lead users to malicious content. The ML classifier strongly indicates maliciousness. The document body is unreadable binary data, but the heuristics and URLs are sufficient to infer a link-farming attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • 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://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a305beb0dae---porawadidegavugufav.pdf In PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160710ced6fd44---kutujunasabaxafudubepuma.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16091ee8a2fcf8---46462099210.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/dofinotez.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/goxisafilodope.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a35b589f19e---56522039809.pdfIn PDF document text
    • http://nissanotogovap.net/uploads/images/files/puvip.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098659b00f8f---20273955637.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c8db673e3bc---83219590061.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/8bc17175cf26cb375118e71b60c09e1d/32430556053.pdfIn PDF document text
    • https://anfauglir.com/images/file/verononuf.pdfIn PDF document text
    • http://galettedesrois.hu/userfiles/file/69309124533.pdfIn PDF document text
    • http://reikihaus.com/clients/75291/File/kesibizutu.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b7553c2879f---9086994358.pdfIn PDF document text
    • https://webupdate.ca/wp-content/plugins/super-forms/uploads/php/files/ec1v1r88cvabh4kmjf4o5j4i58/vevoweroxirugukiguruvogi.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/3cd64e36869f129b255d3578fc800c60/67965189929.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/6670928214.pdfIn PDF document text
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160882ed77829d---xezisigej.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c5e210b76---11897187288.pdfIn PDF document text
    • https://standardpromotion.com/images/upload/userfiles/files/7608584894.pdfIn PDF document text
    • http://autoshiftbid.com/fckeditor/userfiles/file/funedemupijepokamamezijem.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/9c3557843c6bf8a8eb79de4e793c4dd1/58929952594.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=hazards+specific+to+a+confined+space+can+be+categorized+byPDF 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_off00014ec3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EC3 11052 bytes
SHA-256: f59df0a873adb4c938f3dc1419833e09de7bd062a80764737742f17931ca8845
font_01_sfnt_off00016836.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16836 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00018048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18048 17000 bytes
SHA-256: 99bc6f3b3247fecc3bb594f0ba1cc5f876a101d18ffd31c41ba5926185459ca4