Malicious PDF — malware analysis report

Static analysis result for SHA-256 1388211bb21e4ffa…

MALICIOUS

PDF

75.6 KB Created: 2021-09-05 22:13:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 96860117ef1a86e64f4c5e2ecc8301e6 SHA-1: 48c7061c688a97a851249960389722d12f548def SHA-256: 1388211bb21e4ffa7be39d4aec86a87a6073939526f66e61befa0af2c4e108c9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to serve a second-stage payload. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or redirecting users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • 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.
  • 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://irlanc.ru/uplcv?utm_term=the+replication+cycle+of+hiv+pdf
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab35547ec6---76846632254.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076f89a92ee2---zizufe.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ccc49377478---kiwugamibijiruwo.pdf
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d91f4e27c75---41927615096.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611ad82a6c115---31466117461.pdf
    • https://yocarbroker.com/upload/ckfinder/files/nesilotefanowisan.pdf
    • https://vildmarksjagt.dk/userfiles/file/jasujezux.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/h7uv2e80ahhkef4bfhp57frv98/vesizok.pdf
    • http://www.findvoters.com/userfiles/file/sikudiwekusanasotasatak.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4f3e36a71e---87584009936.pdf
    • http://abwingsde.com/uploads/files/mefexujarozufijit.pdf
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d50f0b44082---rarobetojagudarodepeb.pdf
    • http://nfrostov.ru/upload/files/wazezuvaxolubesepinaketat.pdf
    • http://americandeliorder.com/uploads/files/rorefow.pdf
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/17670138077.pdf
    • https://eledigitalpr.it/allegati/file/sitolojubab.pdf
    • http://quatangsongvan.com/hinhanh_fckeditor/file/salisided.pdf
    • http://eclickapps.in/userfiles/files/nusaguxetin.pdf
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608ceab4256e5---gogepe.pdf
    • https://www.stock2morrow.com/ckfinder/userfiles/files/febuvibinumopukuxazisali.pdf
    • http://48bulls.com/js/upload/files/degemije.pdf
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/5acc749253cd53eb69d7abaac958a7e5/zukanegokader.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c212.bin
4c53b6f9fe440d1203deb983e04441f0069deb9ebb0b36b7596a51dbb1ac6246
pdf-font-stream PDF embedded font (sfnt) at offset 0xC212 10692 bytes
font_01_sfnt_off0000da8d.bin
db482a1d776c694c335781789cb4ceabe983f162a2f8c499b8d333c1035e11e5
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8D 18668 bytes
font_02_sfnt_off0001091c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1091C 16792 bytes