Malicious PDF — malware analysis report

Static analysis result for SHA-256 4497c7af114d3b1c…

MALICIOUS

PDF

83.9 KB Created: 2021-07-07 23:17:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: a2d6ece5f6760ee10142a89b1cf57144 SHA-1: bd237cb4849534a0d1887cd49156cd9101b8472c SHA-256: 4497c7af114d3b1c722c352e72d54144385780440c7cae1b10f40a46187a8724
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 sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The embedded JavaScript is likely used to facilitate these redirects or further obfuscate the malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6d6a63553---34208166727.pdf In PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160891430d7220---14791651272.pdfIn PDF document text
    • https://landatur.com/files/galeria/files/fefavutogifawerujuwunoz.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f59092bd35---57782518269.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/90433313314.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5ec563801---15756295237.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0272acde25---14554088422.pdfIn PDF document text
    • http://beateromer.com/bilder/file/25772801746.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/borujijidilo.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/07f2c630ff8bbb1bd66349dce2507743/49308192280.pdfIn PDF document text
    • http://esistore.be/userfiles/file/kojofamakomapuxamavimuf.pdfIn PDF document text
    • http://giaodantanthaison.com/Images_upload/files/12595541382.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/35787595274.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/2b1164990f2c6b4621ffa6466e0b41b6/dugeputesujoped.pdfIn PDF document text
    • http://www.aluvascientific.com/UserFiles/file/26110303628.pdfIn PDF document text
    • http://luisacortesearchitetto.it/userfiles/files/5446944943.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad9dbaa228d---bosudozemotozejebimo.pdfIn PDF document text
    • http://nawaress.com/webroot/js/ckfinder/userfiles/files/83272698342.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/0efc95bfc167de0f3ebcd267146653e3/dulopinakebaxu.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/tubebubi.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/32423961425.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/160806c5c638c7---muzitewunobatuduruv.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb79be0980---50404180102.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/588875f692cf996bd9a5f6aa6e7fb421/93891995670.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc0bb3847b---4190747447.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16072600d88144---velidajejave.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160d5b2e58cc32---98601623266.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=trachoma+meaning+in+marathiPDF 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_off0000e5e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5E8 16700 bytes
SHA-256: e813fb6bfe28ee89b38497401a3060f9068a658e06d2fa643f434b1cee08bb39
font_01_sfnt_off00011105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11105 10428 bytes
SHA-256: f17da231cf659d15bca2c71e8e335b57017a09e41aa396a1b319c4a02d36df28
font_02_sfnt_off0001287e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1287E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1