Malicious PDF — malware analysis report

Static analysis result for SHA-256 9432dc67ee0040a7…

MALICIOUS

PDF

72.0 KB Created: 2021-09-06 00:35:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 46507f0d6f917f45442f4808e9148f4a SHA-1: 9b2fc481423ed7d1aef717a4965ad671bb8a0870 SHA-256: 9432dc67ee0040a7417f37a80d9f601c28b59424f884d6dc94773f456f003160
156 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to websites hosted on compromised CMS upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for link distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.twibiotech.com/plugin/ce1/ckfinder/userfiles/files/nikarafomewudawekakaturem.pdf In PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/tibumerejonitubunibi.pdfIn PDF document text
    • http://broadmoor80.com/clients/866172/File/nozekarulo.pdfIn PDF document text
    • https://melz-feu.ru/upload/vigipixodobosatodigok.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202108102351467115.pdfIn PDF document text
    • http://www.toeterloeh44.de/files/pasutajarosodoxa.pdfIn PDF document text
    • http://thegreenlegacykeepers.com/clients/e/e8/e8dc17949b7ef813e9937e453902477f/File/fuzexobor.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/66720640954.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/53621124794.pdfIn PDF document text
    • https://planet-for-events.de/userfiles/file/958776477.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160822b4ff15c5---61103163145.pdfIn PDF document text
    • http://hopkinshigh1966.com/clients/1/10/1054c114374c88b4a165e91103565d41/File/tujeboregunuxovo.pdfIn PDF document text
    • http://prosquash.by/data/77099799359.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/binusikuru.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160993967adff7---80461145677.pdfIn PDF document text
    • http://hevolta.com/upload/file/37437219049.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf7d82fd77---6775262146.pdfIn PDF document text
    • http://hvezda-pardubice.cz/files/file/42393650985.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/76918955086.pdfIn PDF document text
    • http://thayloilocnuoctaihanoi.net/upload/files/3098847209.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/gjdvefvpikummvoq27941e4m05/fikikep.pdfIn PDF document text
    • http://etcad.net/np/upfile/file/99317562583.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b59212cdc---zigobakuvolizaji.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210603195726192.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=liquidos+y+electrolitos+pediatria+pdfPDF 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_off0000b781.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB781 16892 bytes
SHA-256: 3fbf3f4facdc84abd4e72879a39545d7fd533218b9049d451315072f264cfb41
font_01_sfnt_off0000e1ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f9c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C2 10828 bytes
SHA-256: cf66d2fa92f5da9c1c00bb65da34fce03ee57e9bc0c50dcbf058170936ee5a4a