Malicious PDF — malware analysis report

Static analysis result for SHA-256 92353c3e3d65d4d1…

MALICIOUS

PDF

74.2 KB Created: 2021-09-10 06:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2e153fe9a2e6ff0b5c64bfaf84cd631c SHA-1: e449bdcf66539a6a808f5eec1c1ebb6c3393a743 SHA-256: 92353c3e3d65d4d1d78997be03775872a944eece38ce696fd0f2d109218a30e6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. The presence of numerous external URIs, many hosted on disposable domains and configured as link farms, strongly suggests a phishing or malware distribution campaign. The document body is heavily obfuscated, but the heuristics indicate the primary function is to redirect users to external URLs, likely for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crewmak.ru/uplcv?utm_term=statistics+for+ml+pdf PDF link annotation
    • http://zgic.ru/!upload/files/jaxobuzitidufif.pdfIn PDF document text
    • http://spprp.pl/userfiles/file/posizosubeginusi.pdfIn PDF document text
    • http://shophouse.info/images/files/95234192295.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090514451948.pdfIn PDF document text
    • https://soi.icami.mx/ckfinder/userfiles/files/rirolenu.pdfIn PDF document text
    • http://ipsaix.com/ckeditor/ckfinder/userfiles/files/sudita.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/farumogemam.pdfIn PDF document text
    • http://rigosarchitects.gr/userfiles/file/34039772364.pdfIn PDF document text
    • http://www.neoneofitou.com/ckfinder/userfiles/files/vogukegakupibetapo.pdfIn PDF document text
    • http://sinorarechem.com/upload/files/kerumetusodaz.pdfIn PDF document text
    • http://yung-shun.com/userfiles/file/nezifawavutedexu.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9fca6cff1---mavaw.pdfIn PDF document text
    • https://bimstudioinc.com/media/files/21983267978.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/64927933945.pdfIn PDF document text
    • http://neodentpetrosino.it/userfiles/files/wadalisejufexuxusir.pdfIn PDF document text
    • http://haai.org/upload/file/buzanumopalij.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/85983413932.pdfIn PDF document text
    • https://mcq-exambd.bdbabymart.com/app/webroot/ckfinder/userfiles/files/jegujasideru.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/07a33246ca335455b76a6f06d5ee92b8/vugogegakaza.pdfIn PDF document text
    • https://trainova.com/userfiles/file/novaterukejemagabamil.pdfIn PDF document text
    • http://gocreate.termall.pl/upload/fck/file/disevelevakodovuxixexab.pdfIn PDF document text
    • http://idominjazz.com/fckeditor/userfiles/image/degimuzugemumazebuvexakom.pdfIn PDF document text
    • https://himalayanespresso.com/espresso_ckfinder/userfiles/files/jagunidu.pdfIn PDF document text
    • http://poketomecam.com/uploads/files/34180115960.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///muvevuxexaz.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_off0000c007.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC007 10620 bytes
SHA-256: f1449cd032cc46e24c6b1092e681b5aea56c565a11c791396cc362243f501f4b
font_01_sfnt_off0000d845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD845 16536 bytes
SHA-256: 6f20ed7a40af01797ea9019c2107266c4cf1ea9282e7861b2993c4a8c6d33b4c
font_02_sfnt_off0001031f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1031F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1