Malicious PDF — malware analysis report

Static analysis result for SHA-256 516a52801b365237…

MALICIOUS

PDF

80.9 KB Created: 2021-09-12 01:28:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 15ddc2efefae3ffa810316b74926c9c8 SHA-1: 4f265808542d74948cecbac2f44e6a33f0b804b3 SHA-256: 516a52801b365237e558a47f3c75d79da05c97c15316f06d1cde84a511c8c3a0
156 Risk Score

Malware Insights

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

This PDF was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The document functions as a link farm, containing numerous URLs that point to other PDFs hosted on compromised websites or disposable domains. These linked PDFs likely serve as lures for phishing attacks or further malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://queure.ru/uplcv?utm_term=android+restore+deleted+messages PDF link annotation
    • http://childconnect.com/swi/fckfiles/file/72327049121.pdfIn PDF document text
    • http://saikunghouse.hk/userfiles/gikug.pdfIn PDF document text
    • http://osingenieria.com/images/admin/file/fulawuxuj.pdfIn PDF document text
    • http://harringtonassociateslaw.com/Test/JabzMedicalBillingService/userfiles/file/40912885367.pdfIn PDF document text
    • http://yingtailong.com/upload/file/210909205809721721wof16sjx5itd.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/fd229ff8aea4b9a918ad947a1d2bbcff/ledisaxedunu.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137617777557---68586586576.pdfIn PDF document text
    • https://skopjemuzikon.pmgrecordings.com/ckfinder/userfiles/files/72768949459.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/dogirujosiwida.pdfIn PDF document text
    • http://dienlanhlongan.com/upload/files/1461148909.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/6895721322.pdfIn PDF document text
    • https://ms2oke.com/contents/files/losobejato.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132feace3caf---74693733806.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/48652382882.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/22918563995.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a88409656f---firut.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613bca669468a---fidesiluxedufosixuw.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/sojuvavev.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/povedizigibateliz.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_off0000d64f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD64F 18604 bytes
SHA-256: d1f63981fd41d9763a3a9d0df90648488a3c22e4a6acbcfb6a8834ea01fbd076
font_01_sfnt_off00010670.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10670 10572 bytes
SHA-256: 8c4339ca440f9d34b8c74bd716f13317bbf046f90552b0c2be005914f71b56f5
font_02_sfnt_off00011e58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1