Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bfe5e5f993dcd98…

MALICIOUS

PDF

78.7 KB Created: 2021-09-07 11:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 79349749540e6c5c744f9f5146900bc1 SHA-1: aaea59598c22cf7f46141218bd65338fc3964624 SHA-256: 4bfe5e5f993dcd98ccdea59142a6a9b13638716cf0279bafe0b3c7bcf75e515b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristics indicate the presence of external URI links and a link farm pointing to compromised WordPress uploads, suggesting the PDF is designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly support its malicious nature, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://laborke.ru/uplcv?utm_term=dreams+by+langston+hughes+worksheet
    • http://phongkhamducphuc.net/images/files/4790152225.pdf
    • http://lordbeaverbrook1973.com/clients/76835/File/58412982902.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/55372d1318921567a37edd2da5fe8cd6/2104225818.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/h1kdtu8153vngp78tbbakmls1h/81126881490.pdf
    • http://tamker.hu/userfiles/file/wuzatuzejo.pdf
    • http://goref.ru/files/file/fukilefutugeluwupowedew.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a361e56df0c---lapewujiritusoravo.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093dfc8c1314---banorebagugusurufolatemu.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c499f744d1b---kadasowosijorifebufolud.pdf
    • http://vipdiler.ru/files/file/92674854434.pdf
    • https://felicitareonline.ro/ckfinder/userfiles/files/tobolo.pdf
    • http://abwmercury.com/uploads/files/vajogekafofunukobojuboxa.pdf
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/72912206155.pdf
    • http://amandatour.ru/js/ckfinder/userfiles/files/22626493324.pdf
    • http://portalpr-b2b.es/img/user///file/_0841664001625179099.pdf
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/14a6ac03d265c3ac893f48d30059741d/31498172359.pdf
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/dgu7etksintkav1ijs24f6mi87/72013227549.pdf
    • http://jakebenmd.com/clients/0/0e/0eef9d569b11303d075d19626cc6f958/File/40588233273.pdf
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a935a139a---62307522707.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160849dcc44214---rexive.pdf
    • http://espacioschillout.es/images/admin/file/11864923073.pdf
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd3d4a7bd2---99247647240.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_off0000cee4.bin
254fbd8457c0d5f44815853ab2ad9e1528647597a3b55c4d892639ce09f543a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEE4 17464 bytes
font_01_sfnt_off0000fb68.bin
0e100714284931052f9ed6f6054a2959a3b172e53ec9b48b57f827bc57a080b4
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB68 10996 bytes
font_02_sfnt_off000114ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x114ED 16792 bytes