Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c1d90878617f85b…

MALICIOUS

PDF

79.6 KB Created: 2021-10-17 02:36:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 2647463c09d852be2d9fc152b27448b8 SHA-1: 09505327a8084ea5453765d4b8fbd3f5c87b0eb4 SHA-256: 4c1d90878617f85b7131ee54675ae193acd88750fefb1d58864e51e7c2ba808c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://inwebjor.ru/uplcv?utm_term=blue+chip+india PDF link annotation
    • http://gkz-crimea.ru/userfiles/file/dijoluduti.pdfIn PDF document text
    • http://hqshop24.com/userfiles/file/58355719366.pdfIn PDF document text
    • http://karpatskiles.ru/store/files/jotox.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/64409039597.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/b82b207d277ff3177c35a83d30df3c05/16332751445.pdfIn PDF document text
    • http://hamkr.com/userData/board/file/nipal.pdfIn PDF document text
    • http://nationalherbo.com/userfiles/file/mutolezokuzitasupab.pdfIn PDF document text
    • http://image.dlib.vn/libedu/news/bachviet/20211007/file/38700744483.pdfIn PDF document text
    • http://slmj8.com/data/userfiles/files/80301629756.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/12676351806.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/dogugidarurawa.pdfIn PDF document text
    • https://km2804.com/ckupload/files/ketakepam.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16160336356985---67474039067.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/rosomojonaxagetim.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/sepamawaxanizipusuzexusu.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614b36d206b0d---novovilofikozulodu.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/78950260228.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/59713791083.pdfIn PDF document text
    • http://panziofabian.hu/fck_kepek/kexakufawimefamizivi.pdfIn PDF document text
    • http://gabortech.com/admin/file/wezijuwev.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/95666084048.pdfIn PDF document text
    • http://trieuduong.com/images/Download/97531682850.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1616544feaee94---65933758247.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_off0000d4f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED07 17272 bytes
SHA-256: 0b834135b5a07744d7056363f5155033c5c45f2e817ce43d513ba6dc8f7e9783
font_02_sfnt_off000119c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C4 10276 bytes
SHA-256: 8994a2da0f73f9ac5db9aecbda96492aaaa78ff7c0a632f94f06b586635f9304