Malicious PDF — malware analysis report

Static analysis result for SHA-256 09540bf079dc2b36…

MALICIOUS

PDF

84.3 KB Created: 2021-10-08 23:14:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d9dba16a4f96171ac1a6fea1e353726f SHA-1: c5d507a9f4374a5487b82979e24d28b3b091f8c4 SHA-256: 09540bf079dc2b365d6410705a539c13e36be3416ac421ec6070f4e5633be1ab
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript 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, and the presence of JavaScript suggests it's used to facilitate redirection to malicious sites. The document body is unreadable, but the heuristics point to a link farm designed to lure users to external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://garglob.ru/uplcv?utm_term=gallstones+affect+which+body+system PDF link annotation
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/19819908729.pdfIn PDF document text
    • http://xn--22cjbbm2eyae3ehabdb4kqdtae3dxnnc1fhf.com/user_img/files/ruzutofukijibusakunegi.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/54298090034.pdfIn PDF document text
    • http://iberia-ex.com/images/blog/file/ruzaviputa.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/15285359296.pdfIn PDF document text
    • https://bdprescription.com/ci/userfiles/files/70784500855.pdfIn PDF document text
    • https://mimpidia.com/contents/files/8347096725.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1615f54d6be1ba---44401650406.pdfIn PDF document text
    • http://dspec-car.com/js/upload/files/jolavareguxem.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210912_5AA591D3B8954384.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/14868505296.pdfIn PDF document text
    • http://noavarservice.com/ckfinder/userfiles/files/vasasulibe.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/161408e10e71af---fegemeloderaxirufatulug.pdfIn PDF document text
    • http://thepducphat.com/upload/files/fajaxowax.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/17078424941.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/ba348a2126a7030f9084d477a7f0d859/34109279879.pdfIn PDF document text
    • https://heritagecambodiatravel.com/userfiles/file/33813980061.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/bc77fa5f49ef5b8d09f3b4a377d36553/83457072507.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/17759062748.pdfIn PDF document text
    • https://oykufestivali.com/ckfinder/userfiles/files/4539854570.pdfIn PDF document text
    • https://kimcert.org/E/file/21738765311.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/86040390129.pdfIn PDF document text
    • http://biosystech.com/pdsFck/file/matelij.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109211222304338.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_off0000dedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEDD 11020 bytes
SHA-256: 66d27219d9480f8e7de9eaf9cfbfd7ba8bf5e282d7624989f0367ccdca659460
font_01_sfnt_off0000f86a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF86A 19432 bytes
SHA-256: e2e6e51f9a4efb3023420866cd52064eb118a29d2f1ad065e1003809b9888844
font_02_sfnt_off00012b30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B30 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1