Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbfdc3a331ddedea…

MALICIOUS

PDF

74.7 KB Created: 2021-09-17 12:20:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 78957675681222695163c54e8b9c5d15 SHA-1: 77645057445375d92696e0bf3d83998d52e65469 SHA-256: cbfdc3a331ddedea986750b0d8286c8845b5aca94e2026fd368373fcd324ce29
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites and other disposable hosting, a common tactic for phishing or distributing malware. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan. The embedded URLs suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://tramhuonghanoi.vn/upload/files/figuda.pdf In PDF document text
    • http://1day2night.com/UserFiles/file/63432283439.pdfIn PDF document text
    • http://bakoca.hu/files/file/57602591421.pdfIn PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/dobip.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/q21njlqsst9iac49tfglj0vqgr/37094848556.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/64962929905.pdfIn PDF document text
    • https://stka.gr/ckfinder/userfiles/files/2947002570.pdfIn PDF document text
    • http://maschimaurizio.it/userfiles/files/sadonas.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/zazaxosewegasexovone.pdfIn PDF document text
    • http://fxmeat.com/upload/file/3ea1f914a122d7d03aefe6bbf4c896e5.pdfIn PDF document text
    • https://arhstroi.by/uploads/files/vabiwe.pdfIn PDF document text
    • https://solener.info/ckfinder/userfiles/files/39307215825.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/85640166836.pdfIn PDF document text
    • https://esofagopisa.it/userfiles/file/91262415671.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/0bbbc051237a5f52d753316a7550b2d1/kebew.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/h3h29smo20lo1icr178ar9cm68/26152891815.pdfIn PDF document text
    • http://interno-kazan.ru/upload/files/32866882224.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/9711910882.pdfIn PDF document text
    • https://ever-progress.dacola.com/upload/files/49072545336.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/kediz.pdfIn PDF document text
    • https://krainaogrodow.eu/zdjecia/fck/file/dotuduvapaxev.pdfIn PDF document text
    • http://hoangnampte.vn/quangbasanpham/app/webroot/upload/image/files/6957800403.pdfIn PDF document text
    • http://gzlmjx.com/data/home/bxu2343160066/htdocs/uploadfile/files/99585723371.pdfIn PDF document text
    • http://fanta-life.com/userfiles/file/xodonoderepunobajixixami.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161375c1a2c421---luwelebamokugas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=merck+index+pdf+ebook+free+downloadPDF 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_off0000c0eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0EB 10760 bytes
SHA-256: 2a25b8b99f15cd57dc77ef5487660a32473c4f5b1e55745c1a966dfda6c5fe5a
font_01_sfnt_off0000d993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD993 16512 bytes
SHA-256: fba94c51e5ea4f29e83434e6294bd35ae702d7230b50733ceea216209a32e24c
font_02_sfnt_off0001048e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1