Malicious PDF — malware analysis report

Static analysis result for SHA-256 2371cba308fb91a3…

MALICIOUS

PDF

92.7 KB Created: 2021-08-08 19:08:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: b86608bbe69eae9369a45c42ff0e5a1b SHA-1: 83c7a1125ba5de71d76cadc6521a4fa854aed222 SHA-256: 2371cba308fb91a3af565f51b253108dd6d19cbd63a65c64d338cda5ffccbc14
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing an embedded JavaScript stream, which is a common technique for executing malicious code. Numerous URLs were extracted, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://synerhu.ru/uplcv?utm_term=poema+de+lengua+indigena+y+su+traduccion+en+espa%C3%B1ol PDF link annotation
    • http://importfoodfair.com/userfiles/image/2021/08/file/gomomawot.pdfIn PDF document text
    • http://pozitron-s.ru/userfiles/file/dodepej.pdfIn PDF document text
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/f33d882a5fd27ee828bd6dbd374de26a/79981530792.pdfIn PDF document text
    • https://mimpishio2bet.com/contents//files/15909380644.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/58456478233.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/55766267555.pdfIn PDF document text
    • http://sehs67.com/clients/e/e0/e078d4d0076166a7bb489ca3b3a583ab/File/kexavavekobipemukifo.pdfIn PDF document text
    • http://www.celso.org/download/69825414378.pdfIn PDF document text
    • http://hawks79.com/clients/85064/File/refesebum.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/25816388264.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/sarobomiwerinoxulesif.pdfIn PDF document text
    • http://markone-tools.com/upload/files/72502836696.pdfIn PDF document text
    • http://brlairport.com/images/file/73836222420.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/16072c8cd9eaf7---27426323518.pdfIn PDF document text
    • http://bafiti.com/sklep/userfiles/file/zabimiru.pdfIn PDF document text
    • http://bonfiremadigan.com/uploads/fckeditor/file/21054504516.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/61d1cbbac20b637cc175e4e6a117f744/21845319025.pdfIn PDF document text
    • http://shiinamotors.com/js/upload/files/podixarakewev.pdfIn PDF document text
    • https://vettercycles.ch/userfiles/files/59198635540.pdfIn PDF document text
    • https://chp-travel.ir/data/file/popavunovikif.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/80114204080.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_off00010034.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10034 18944 bytes
SHA-256: 744329ab478c5e5585dbd8528bff06c02f1fad00eaa42c24c12c21c2270fff34
font_01_sfnt_off00013087.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13087 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001489e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1489E 11280 bytes
SHA-256: 7f6642b14f5bd42097a0d54d29913890b4402f1af310a6858eec75c85f616f30