Malicious PDF — malware analysis report

Static analysis result for SHA-256 9589a363b06cddbf…

MALICIOUS

PDF

87.5 KB Created: 2021-09-09 17:49:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9d08b7e73629c487f2f450942e73c967 SHA-1: 39a158abc3958f955f026a58ec620d9b3bc7ef84 SHA-256: 9589a363b06cddbf21ee7aba5840322c29a509053e1410eb9ec5f57549ebac80
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many of which point to websites hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://noithatdangcap.vn/app/webroot/uploads/files/47646522705.pdf In PDF document text
    • http://yizhu580.com/ckfinder/userfiles/files/92881203828.pdfIn PDF document text
    • http://bilcafe.it/userfiles/file/2804551443.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161340e14a2917---jesunufatuwagofiful.pdfIn PDF document text
    • https://iword.de/userfiles/file/mabofuragal.pdfIn PDF document text
    • https://tjp2-hotlink-j3t.com/contents/files/sebefamugivedu.pdfIn PDF document text
    • http://abwrichmond.com/uploads/files/95805195243.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/gunesivuxojojawumigu.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/patajovima.pdfIn PDF document text
    • https://singlespeed-switzerland.ch/userfiles/files/kasamonedow.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/38717542303.pdfIn PDF document text
    • http://djapm.com/userfiles/file/55616016504.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/73868862745.pdfIn PDF document text
    • http://phonphangschool.com/upload/files/51063060450.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/60047271096.pdfIn PDF document text
    • http://tatagz.com/uploadfile/files/dujevozetoxuxupan.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/161372b31a8941---fibesuzopamuwifimewepew.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16132077cce377---bukawuv.pdfIn PDF document text
    • https://gregoryshow.ru/files/file/sedafufeziperudexaxaba.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/nipikaritanudop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=record+discord+callPDF link annotation
    • 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_off0000f137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF137 18720 bytes
SHA-256: 45e0983ad7800a9c3a5cee6949d6a748b288c3cd9b0a7b6d410895f1a8dacf8f
font_01_sfnt_off0001218e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1218E 10208 bytes
SHA-256: 1a34409b3fa77fd3509701dc71f8e879d138c6052ac4a3fed30f2ab02ddb79fd
font_02_sfnt_off00013887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13887 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1