Malicious PDF — malware analysis report

Static analysis result for SHA-256 b03d23d993bc14d9…

MALICIOUS

PDF

88.3 KB Created: 2021-09-16 19:17:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 0c47f49b6e0a27ef5794f867a78a7968 SHA-1: 40da67c4bf32c8712d742d630e4da16c6f8b6649 SHA-256: b03d23d993bc14d9e0e3707aa57cd648cfffe14bae6d31b269839738969f7ada
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier strongly indicated maliciousness. The PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the nature of the heuristics indicate this document is likely a lure to external malicious sites, potentially for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://crysiq.ru/uplcv?utm_term=excel+to+pdf+best+converter PDF link annotation
    • http://franzoesischebulldoggen.eu/userfiles/file/31669754184.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613519d4c7e18---velutimagonobijakiga.pdfIn PDF document text
    • http://xszhuhai.com/uploadfiles/files/vemigemefosekimisotira.pdfIn PDF document text
    • http://vantaidongsaigon.com/uploads/files/begiremufazonomoke.pdfIn PDF document text
    • http://kuresi-kaitori.com/upload/content_pic/files/janasazubamuxelasig.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/76e70fbpkf1ba1td9ruqj90b94/83040434014.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16141505d91516---72024620592.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/8423983290.pdfIn PDF document text
    • http://greece-ex.com/images/blog/file/99901048436.pdfIn PDF document text
    • https://www.utn.ac.cr/sites/default/files/files/sidutenizife.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/sasuzideka.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/2fb6c9b843f3635d01705143d053a5e3/furolu.pdfIn PDF document text
    • https://www.pepinieres-gey.fr/ckfinder/userfiles/files/79434108993.pdfIn PDF document text
    • http://epilia.com/upload/FCKEditorfile/73519780598.pdfIn PDF document text
    • http://edilcfcostruzioni.com/userfiles/files/gasimizigumebuvurujager.pdfIn PDF document text
    • http://www.arborvitae.cz/ckfinder/userfiles/files/86194365444.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614268e6b2888---44861317904.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613358536d26b---vanibilu.pdfIn PDF document text
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/7033336407.pdfIn PDF document text
    • https://sausalito.com/wysiwygfiles/file/40045630156.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/83736461997.pdfIn PDF document text
    • http://elitvorota.ru/f/file/dujafelibuxexugodalove.pdfIn PDF document text
    • https://digitaluzaktanegitim.com/calisma2/files/uploads/41615898700.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/60804563661.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_off0000f5e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010df8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF8 10648 bytes
SHA-256: 826ca37b32a6aa8f6fba772910833bacfe491547dc58f8a8b0701c6e551cece1
font_02_sfnt_off0001264c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1264C 17484 bytes
SHA-256: 46ccf8e5d4d4fd6fff730c12f42e2a98cc9f55cd57087532189aecc9a42f37bf