Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e4e98d2e8916324…

MALICIOUS

PDF

82.2 KB Created: 2021-09-18 18:48:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9d0b1eb8aaa3f496122ed54bebdffbd1 SHA-1: ec142f0e446c5a9531cd5699ce6fc0224dc57c90 SHA-256: 8e4e98d2e891632416a12c23ce462a3c6041b2c4ae5ca3392582f5fab4189325
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicative of a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads or lead users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://infrive.ru/uplcv?utm_term=business+english+answer+key PDF link annotation
    • https://limberhurstgallery.com/imageuploads/file/dozufuzumasen.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/xagijod.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1630943676.pdfIn PDF document text
    • https://kurtoglumob.com/upload/file/4512272986.pdfIn PDF document text
    • https://nasco-ye.com/uploads/file/zolepanewivedajifi.pdfIn PDF document text
    • https://kolorubursztynu.kolorubursztynu.pl/web/uploads/files/pawiwubonegifud.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/81703082797.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/wibewasegisor.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb3c9c99d4---kerurudezanunam.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133258e4fdac---jajikobabuj.pdfIn PDF document text
    • http://camara.acessoainformacao.org/uploads/ckfinder/files/gasemasuvafobojusume.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/81714314844.pdfIn PDF document text
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/65667699163.pdfIn PDF document text
    • http://centrlita.ru/archive/image/file/99328093520.pdfIn PDF document text
    • http://beta-rc.com/upload/files/66357814295.pdfIn PDF document text
    • http://raczcsalad.hu/files/gudagevedud.pdfIn PDF document text
    • https://xn--b8qxb801j.tw/upload/files/wozuxizixuvokodisugu.pdfIn PDF document text
    • http://dasbluemchen.com/49907069274.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f78823da6f---12566571742.pdfIn PDF document text
    • https://linardi.ru/files/file/24974668545.pdfIn PDF document text
    • http://xn--12cmi2byac9cdhd0hra6d7bxkwbgj1gch.com/user_img/files/sobega.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/defajuxufowofozar.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_off0000d78f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD78F 19988 bytes
SHA-256: 785a5d80548600fd1e6d3d280faeefbe3973f7fbc695f3fbd7e8b359f14b4880
font_01_sfnt_off00010b3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B3C 10616 bytes
SHA-256: 72aa541b85100eb628edbf84f1910af0ec0957cd86dee3228ff5691d2dfdd970
font_02_sfnt_off0001237f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1237F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1