Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cd51f60d0f3e478…

MALICIOUS

PDF

77.8 KB Created: 2021-09-18 17:34:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1b0b9e8b9b41f6d3351c463882f5d3e1 SHA-1: b489d39d7d632ec1e8d308d454549cbb3931ce95 SHA-256: 4cd51f60d0f3e4785c77b867e2411b4292a33cd79dc782d4f3c4f53f4ac5c6f0
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress uploads or disposable hosting, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple external URIs and link farms points towards an attempt to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://crysiq.ru/uplcv?utm_term=converter+mp4+to+mp3+online+gratis PDF link annotation
    • http://kurskodkb.ru/page_edit/_samples/userfiles/files/makopafibaselux.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/fd404c0b885ffb3289f95926e5535704/suxenakuvisaresinube.pdfIn PDF document text
    • http://deshdunya.com/blogimage/file/telujoseduf.pdfIn PDF document text
    • http://rayhovietnam.vn/upload/files/rukugodivunixefewadeviwu.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/jotosexo.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/nolotu.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/dolerazenirefuz.pdfIn PDF document text
    • http://agilesolutions.in/uploads/xapukimetaxuli.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161329a6256425---6800642509.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210905174955.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/16052727933.pdfIn PDF document text
    • http://kammatrans.com/userfiles/files/jedadoludul.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/ruvenedekikodedez.pdfIn PDF document text
    • http://metabolitplus.ru/files/file/37206276648.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/1584661573.pdfIn PDF document text
    • https://hmanagement.net/userfiles/file/46359589275.pdfIn PDF document text
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/12541125343.pdfIn PDF document text
    • http://157.230.241.115/image/upload/File/tujuxavolutatun.pdfPDF link annotation
    • http://thesecurityguardunion.ca/userfiles/files/24184640748.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/sanilebijofosimo.pdfIn PDF document text
    • http://zhuxintrading.com/uploads/ckfinder/files/20210908/16310535115966.pdfIn PDF document text
    • http://cga82.com/admin/File/migijemadivudadoneninuve.pdfIn PDF document text
    • http://centrons.com/uploaded/file/361513470613ec1271d447.pdfIn PDF document text
    • http://schule.havonix.com/ckfinder/userfiles/files/nosezijibunup.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/161452d4a4bcb6---bimaxubowu.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_off0000cae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAE0 10944 bytes
SHA-256: 31584abdd657c1d74a4ab7e99ceed55a7459e718da2248c1de1ce4a42484f16a
font_01_sfnt_off0000e455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE455 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fc67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC67 17336 bytes
SHA-256: bc9002ffa4034a7e9b544651b0d7bd258612e44abb5f452b2d7a68dae2213d47