Malicious PDF — malware analysis report

Static analysis result for SHA-256 7dcd10ab92478a1f…

MALICIOUS

PDF

82.4 KB Created: 2021-09-09 15:10:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 675a15aaec3abd4e7b7b7ea1a200c0c1 SHA-1: e48a5482f5b391c7511d05632e2217fbdf30e65d SHA-256: 7dcd10ab92478a1f198933081b3912200884b19957a7d34f84439b398425bffa
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://krisoc.ru/uplcv?utm_term=games+ppsspp+download+free PDF link annotation
    • http://jar-ted.pl/file/kamujevejowonudinat.pdfIn PDF document text
    • https://sunsetlearningcenter.com/userfiles/file/184971775.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/degudevadulu.pdfIn PDF document text
    • http://1qjd.com/upload/files/2021-09-08-12-33-15-xhcrr3a8.pdfIn PDF document text
    • https://ntct-dz.com/ckfinder/userfiles/files/88496514596.pdfIn PDF document text
    • http://sdes.in/uploads/pamenusemuwapujuji.pdfIn PDF document text
    • https://journalofcritique.com/ckdosyalari/upload/files/44038336665.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613012f23cc62---16544980179.pdfIn PDF document text
    • http://tieuhocsongphuong.hoaiduc.edu.vn/ckfinder/userfiles/files/vareridujegexonuwevut.pdfIn PDF document text
    • https://justforjetscatering.com/userfiles/image/files/totulojipetirowufoduz.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/29760062541.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161382523295a0---zesurodafewarelojeg.pdfIn PDF document text
    • https://viscom.bg/uploads/wysiwyg/files/sagezizuvopepusenoz.pdfIn PDF document text
    • http://conservativista.com/js/ckfinder/userfiles/files/gobixodizudurorofube.pdfIn PDF document text
    • http://orderbestwings.com/uploads/files/73881696934.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/gulakitubukibo.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/abd8e29165661d41dd9e3e27fcc9231a/95880376938.pdfIn PDF document text
    • https://unaizahic.com/Files/files/4889718632.pdfIn PDF document text
    • http://surausa.com/uploads/files/37357143576.pdfIn PDF document text
    • http://innotack.com/userfiles/files/diligefugovasemanelisajus.pdfIn PDF document text
    • http://myxroad.net/upload/userfiles/file///38636636106.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/14405526068.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_off0000de0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE0E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f620.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF620 17696 bytes
SHA-256: 29ecb09ab7e7f3d5f3c9ed5f4db3dd6100c33aac8a7f9dc8623e673bbb836ea6
font_02_sfnt_off00012405.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12405 10592 bytes
SHA-256: bc70c883ef1bce6a2a7f3f5684a7a16c421dd5ad11a9c1aabeef36b58e9152c4