Malicious PDF — malware analysis report

Static analysis result for SHA-256 c158ebf430140e38…

MALICIOUS

PDF

87.2 KB Created: 2021-06-30 03:58:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 07931801d922974a180d5cb88fa4707f SHA-1: daeddb48c3deb4b287c1336e4c2ee8e939f7fd45 SHA-256: c158ebf430140e3884343f8be2334795846de17e50ac1496e1067152a91471e5
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to domains associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://garglob.ru/uplcv?utm_term=barron%27s+this+week PDF link annotation
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/vcph29c8a6a8svbd85q6mjb6g3/4312311799.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/46a8349b75ec90bad95537f9a7dbc4d3/dafatizamel.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/74988866878.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cdcb9de00fb---61036460753.pdfIn PDF document text
    • http://beiwendq.com//data/attachment/file/57496765319.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/34255163572.pdfIn PDF document text
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/gexafudesazer.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/a3391f8da30f771c193076d9647b23ca/83380328102.pdfIn PDF document text
    • http://granite1962.com/clients/869125/File/92713318713.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aac40e83ca1---64251153930.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/1j1uoab4f2umh71bo7g4a8ijlo/6620336849.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083fea7f38b1---mejifozepanu.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c694e25f5---fapuwebakixif.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/66227727885.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/63822595571.pdfIn PDF document text
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/29778079946.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f7c0150ab---mekox.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a19cb49cb43---rorevora.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac506990b2---59199007357.pdfIn PDF document text
    • http://10glazsikeyrosa.ru/file/mewupotodujag.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160721046be046---52979684984.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f165f723a9---pijiwuzabirazazepudumofax.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aeaa629abac---xamonagaxobitulikemuna.pdfIn PDF document text
    • http://teaandtiarasottawa.org/clients/e/e8/e8f54e69a7463df9fd0adff13cd8e90f/File/wotilimarijibaxozeved.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_off0000f031.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF031 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010848.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10848 10424 bytes
SHA-256: b2011c8ae215a4df253f7938dfaeafa58717276150b827b16b52a809f3ce0abe
font_02_sfnt_off00012000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12000 17808 bytes
SHA-256: 947e2665df3ed2332f5c9238b21d621914d9f89e4cbf722745f7a846534960bf