Malicious PDF — malware analysis report

Static analysis result for SHA-256 c66723ac368910e5…

MALICIOUS

PDF

71.5 KB Created: 2021-10-01 11:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 26cf13b7d60d6acf6c41b28ff3f5f788 SHA-1: 996fbab801e761501d352ab2f792b96186d6d4b4 SHA-256: c66723ac368910e5d996e0f4df907fbc5586c83e9e4e43f4a011e9e6ab9b8b6c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a significant number of external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The embedded JavaScript likely facilitates the redirection to these malicious links, aiming to trick users into downloading software or visiting phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://catamma.ru/uplcv?utm_term=powerdirector+pro+apk+full+version+free+download PDF link annotation
    • https://espiber.cl/images/uploadedimages/file/27985919441.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/19431805991.pdfIn PDF document text
    • https://ihappywash.com/uploads/files/202109132048167177.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/67939291236.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/nurejugipiz.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/72470953598.pdfIn PDF document text
    • https://narellesastro.com/userfiles/files/sidasapuxuwukube.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/ccd0c693f3c321157010d78f40b102b5/guvozed.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/43388145859.pdfIn PDF document text
    • http://aokunoil.com/ckfinder/userfiles/files/39772097208.pdfIn PDF document text
    • http://nawaress.com/webroot/js/ckfinder/userfiles/files/48366676454.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/lufokipowapipufit.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1631484119.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/70404864590.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/gewavunazujigubizizap.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134e187eb6b5---nogovabutewed.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/daboxoguluteruxagaputok.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/faxevo.pdfIn PDF document text
    • https://laetitiabernard.fr/images/file/luvajumonofimaji.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/750cf320e807a42cf1a0581f1468e6f2/92071221868.pdfIn PDF document text
    • https://digireg.ru/upload/84250056240.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161425b0610bde---zaxotowukiromejemupog.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/lisagibutedat.pdfIn PDF document text
    • https://yp05.com/_UploadFile/Images/file/nitoz.pdfIn PDF document text
    • https://trongtrucsolution.com/uploads/files/fuzekuk.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_off0000b371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB371 10960 bytes
SHA-256: 57c51ac51b23148615e169d502c5dfb1445ed1653e04076bcee4bb82229d84c6
font_01_sfnt_off0000cd1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e52f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52F 15968 bytes
SHA-256: 2e3e81924e6625bda37e94cefdf0af269144ae6fa21d3861038b85a29ff84eeb