Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4e1cf0ffb09ab9f…

MALICIOUS

PDF

87.2 KB Created: 2021-09-15 17:46:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5c8a5aac9927210073f9b3e0b515c5f3 SHA-1: 2a933cc33de8f94a285b3abdcc3edd24c8d59381 SHA-256: a4e1cf0ffb09ab9f3c08952c45b7954dd0d6f73b99c04eba07706fdebed7b610
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or redirection scheme. The PDF structure and embedded URLs point towards a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://coretry.ru/uplcv?utm_term=mx+player+without+add PDF link annotation
    • https://strategie-forex.com/ckfinder/userfiles/files/totaxipagegirojimosi.pdfIn PDF document text
    • https://wmu24.ru/media/file/mazapibe.pdfIn PDF document text
    • https://nghiepvu.udicmanpower.vn/uploads/news_file/1771264434.pdfIn PDF document text
    • https://lodoshosting.com/calisma2/files/uploads/72731576751.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/a31d913f54235398f5515d2e6857d6aa/gonurukedamizutidi.pdfIn PDF document text
    • http://theffirm.com/userfiles/file/sidivivodetubo.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/tukakop.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/25213538481.pdfIn PDF document text
    • https://areopag.ru/sites/default/files/uploads/40704328863.pdfIn PDF document text
    • http://bratislava.topenglish.sk/app/webroot/gallery/files/xobomekumabi.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/5700318417.pdfIn PDF document text
    • https://stl-log.com/htdocs/cljr/data/files/62056919197.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/77241388838.pdfIn PDF document text
    • https://isitekmuhendislik.com/userfiles/file/tetidelofa.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/60097889602.pdfIn PDF document text
    • http://kozelskadm.ru/files/uploads/files/14451905709.pdfIn PDF document text
    • http://cheumst.com/upload/fckeditor/file/rikowewu.pdfIn PDF document text
    • http://safetyassessmentsolutions.co.uk/ckfinder/userfiles/files/pebekesodaxezixikova.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/7558551616.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/wirogipojapaxupurawod.pdfIn PDF document text
    • https://bio86.net/userfiles/fichiers/82949423315.pdfIn PDF document text
    • https://sicurezzaips.it/uploads/file/zimud.pdfIn PDF document text
    • http://labsshop.com/d/files/5072640289.pdfIn PDF document text
    • http://niszczeniewaw.pl/userfiles/file/40019867669.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/11093760345.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_off0000edb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB7 18500 bytes
SHA-256: 9ca825d1dd76b820b07582e241d35a5c023116f667c90781d7adddf26de0e8de
font_01_sfnt_off00011e57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E57 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001366e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1366E 10612 bytes
SHA-256: 037e8daa63a0cddad051a108be05e0ddeabe5d3fbc5248fa5890a62ff3a485fe