Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef51363aa22ef792…

MALICIOUS

PDF

87.0 KB Created: 2021-09-09 01:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: dacc298a52c491346ff56566e90cd6e3 SHA-1: fd2b3c84dc9110f0fc92b53262d34454b4f2014f SHA-256: ef51363aa22ef7926ce6fad74f8aaf0f82fa0ced15b4e252367875ffc1158809
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various domains, many of which appear to be part of a link farm designed to redirect users. The ML classifier strongly indicates malicious intent, and the presence of multiple external links suggests an attempt to direct users to potentially malicious websites for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://huntic.ru/uplcv?utm_term=note+20+ultra+drawing+app PDF link annotation
    • http://beautybybelief.com/admin/images/file/23908255578.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/m9brj1090b86bb98pr9sr6pt5n/25640629211.pdfIn PDF document text
    • http://dui-antidote.com/images/userfiles/file/begigugagamutejanazazesa.pdfIn PDF document text
    • http://hugslock.com/app/webroot/img/files/13646079570.pdfIn PDF document text
    • https://alternativecarrepair.nl/userfiles/file/63060706646.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/mobirigewinuzupaweluson.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/molerod.pdfIn PDF document text
    • http://skonasystems.com/userfiles/file/mitoretarewawo.pdfIn PDF document text
    • http://re-media.ru/foto/ck/files/4104166413.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/525b39797e68c3fece70a4f3bc6427f6/89844394723.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137544a878bf---katozamivepuwukivugi.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f39d328dc6---96312688797.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/27736254750.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/rajolapudi.pdfIn PDF document text
    • http://vstarmp.cn/upload/files/20210905_131620.pdfIn PDF document text
    • https://ht-cooling-j3t.com/contents/files/54867875540.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/kinaxiwukofu.pdfIn PDF document text
    • https://triosms.com/userfiles/file/tolebaguzibelixajuke.pdfIn PDF document text
    • http://sushrutproctology.org/ckfinder/userfiles/files/30386802730.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/jusakova.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/lexotikedanumub.pdfIn PDF document text
    • http://abhinavabhishad.org/userfiles/file/21467933378.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/64102404951.pdfIn PDF document text
    • http://women-for-marriage.com/ckfinder/userfiles/files/jilolomala.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_off0000eb48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB48 18552 bytes
SHA-256: 0cae59e4a061e822c45545b8dc1e56539fcad950a468acb86ed430b51b871888
font_01_sfnt_off00011be9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BE9 10804 bytes
SHA-256: 3bfe0373fe734ba094e477f3ef0b403761c640121373c60fdcf7373c7989c253
font_02_sfnt_off000134cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1