Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b53b11450e72d25…

MALICIOUS

PDF

83.6 KB Created: 2021-09-07 12:28:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 79b83c50e392b30ea532cc2947a50921 SHA-1: 4469ad94d67be19f974fe663331d2576793dac94 SHA-256: 2b53b11450e72d25eadb53665c32d1943b785848ce19b9f51a0db4c031f32f9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to PDF files hosted on various domains, some of which are identified as potentially compromised CMS uploads. The presence of external URI heuristics and the structure of the PDF suggest it's used to distribute or link to other malicious documents or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://palenice.net/obrazky_clanky/file/42506777061.pdf In PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16111f96f2dacd---pilojumes.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210805180136_jxrjc9.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/97157938103.pdfIn PDF document text
    • https://paron-rebondir.com/uploads/files/tapukojunugesedaxejezuvon.pdfIn PDF document text
    • http://kubablimel.pl/Image/files/gexememetedelinaxonijo.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a29e696377a---luvajat.pdfIn PDF document text
    • https://rumputhijau.com/contents//files/ruref.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/zosunewubujibem.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/1a2da2ee0f3cd43ff9df0594a2134dce/nijajalevumapinova.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/0af442fdcccb6cdb2b6467085ee42dc0/vukatetuwumu.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/hcrrb4qvln53dl53ulvqv2302r/64035310213.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/wuxafu.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/c8fda42c5f92dc81ec024963a687096c/41604442505.pdfIn PDF document text
    • http://ovodatar.hu/userfiles/file/33755932885.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/welisavimezisijonex.pdfIn PDF document text
    • http://emke.hu/uploads/ckfinder/userfiles/files/25178559172.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/6d2ea8561e649679380be4a21df1bba7/gaxegevejemuzexali.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/eeoq11ksnpvogtjg5r7qns0pl1/wevimejid.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0a684555b---73180864631.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/fesiwutuxewokuvokaxaxibo.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160f31705bee11---mefedusutefo.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/3db2763287f3e439ff934100184f825d/dixogoxefibek.pdfIn PDF document text
    • http://saikunghouse.hk/userfiles/78217354857.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=algebra+factorization+worksheets+for+grade+8PDF 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_off0000dbaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAF 11324 bytes
SHA-256: 0bcf99f6f66b9b40526c0194e92b0a8432dfa68aaf34ccd0ec945e5ff3277ce7
font_01_sfnt_off0000f62c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62C 18440 bytes
SHA-256: ae2fc9b5ff4cd4e5fa0e93667b2e7dd8d592a69e3eec4e3f893f48621a76f413
font_02_sfnt_off000126ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1