Malicious PDF — malware analysis report

Static analysis result for SHA-256 da4771e3a01073f2…

MALICIOUS

PDF

67.6 KB Created: 2021-05-26 04:38:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: b574c72f40647a0ba297608665b58c77 SHA-1: 6b855d459da8cd47d490fbb067e1c46292717ac1 SHA-256: da4771e3a01073f21c5a72d72d2e53fdf971c98aae4f038094d394a1b8900108
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF document contains numerous links to compromised websites, many of which are hosted on disposable domains and utilize formcraft plugins for file uploads. The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, suggests a lure related to a 'free illustrated biblical dictionary', likely intended to trick users into visiting malicious URLs for further exploitation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://laborke.ru/uplcv?utm_term=nuevo+diccionario+b%25C3%25ADblico+ilustrado+gratis PDF link annotation
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608745a25e879---18085484231.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/3464128288.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aad7505a9d9---wokipamirisadi.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aae64233b6c---visubux.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073611416126---73182153864.pdfIn PDF document text
    • http://ptairsupply.com/userfiles/file/gejuse.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5c782db53---41565820848.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16074fa5035d63---62175427656.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606dcace70f56---94422604971.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1608f85144de83---sesep.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a2eb863c58.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021052111344710.pdfIn PDF document text
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607723e621c94---13459411617.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/41850bd185c528ef271076a431a4df80/41159285824.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/f7e2d252d285f0b17fcb4f0be04cead0/4651397968.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c87d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC87D 5332 bytes
SHA-256: c0bded9489d7bff3293126a264c78f532f566f599ab570b08b8a9f2bc893158d
font_01_sfnt_off0000dabc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDABC 10848 bytes
SHA-256: 9231f952f73b9d55b542f33163e5cf1c56dab8b5c55a998ba7088daa9b0d4533