Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3a64c84596e47c…

MALICIOUS

PDF

85.3 KB Created: 2021-10-10 14:46:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d747d2a88adf9bba0ae81aae867060b8 SHA-1: e2bd4fef2324c670a679c703c6bf248559cdb8f6 SHA-256: 8e3a64c84596e47c370b5e2584af1881577f5ff64ab10d19f48145ea828fdd20
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ML classifier strongly indicates maliciousness. The embedded JavaScript likely facilitates the redirection or execution of further malicious content, while the link farm serves to distribute traffic across multiple domains, potentially for SEO poisoning or to evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://medvor.ru/uplcv?utm_term=diazepam+10mg+how+long+does+it+last PDF link annotation
    • https://alrukn.co/userfiles/files/titono.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/af7rhcp06o608vbmn3cnvlehb7/55924700068.pdfIn PDF document text
    • https://isleo.com/i_photos/file/45789022132.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/44926939374.pdfIn PDF document text
    • http://wonderpanel.com/app/webroot/img/file/97236355486.pdfIn PDF document text
    • http://cofetariafraguta.ro/UserFiles/file/29965398633.pdfIn PDF document text
    • http://seed-hongkong.com/uploads/file/posorurisebixejakejamo.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/roduj.pdfIn PDF document text
    • http://iphysiology.ru/upload/bipaserufuraxul.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea5a965a07---xubufuwiwijojon.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/66381198543.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/34081358783.pdfIn PDF document text
    • https://sfeerweter.nl/userfiles/files/35331037225.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/6e4efaf6d63d1915fb83a8f528577de9/viseluvibego.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/koturelunusuja.pdfIn PDF document text
    • http://labmansour.com/app/webroot/js/ckfinder/userfiles/files/84546780085.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/99159604885.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16150fb237ff3d---vakovujikafarogifagu.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ff18877917---27827151158.pdfIn PDF document text
    • https://minhgianggroup.vn/upload/files/sazogimok.pdfIn PDF document text
    • http://lesen-und-schenken.de/userfiles/files/juzonotigunabusejisi.pdfIn PDF document text
    • https://empresa-venta.hr/files/15914885067.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_off0000e474.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE474 11060 bytes
SHA-256: c652ac3d5c67fc90b5be9a0c2e964978fb1f7faf4926db5f16c3e54454a48991
font_01_sfnt_off0000fdef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEF 18976 bytes
SHA-256: 37a457554f948a134644699809659ae668c7392a4b6bd101198acf6d25cc20bf
font_02_sfnt_off00012f8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1