Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca99b6c510e863af…

MALICIOUS

PDF

88.3 KB Created: 2021-09-09 15:07:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6caf42cab0659bb362e357dd5187d8a4 SHA-1: c82dae14f5a6c4a53a7d62f1f49760200e72be31 SHA-256: ca99b6c510e863af5b5b6752d9e299fdf5d207c1985e86325645e522a4afb91a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of external links, many pointing to potentially disposable domains, suggesting a phishing or credential harvesting attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • 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.
  • 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 http://a1climbing.com/userfiles/files/sipudipoguvogazamomonol.pdf In PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/40144195600.pdfIn PDF document text
    • http://chinahongji.com/d/files/15005148912.pdfIn PDF document text
    • http://canhtoanland.com/upload/files/4963353245.pdfIn PDF document text
    • http://nieruchomosci-swidnica.pl/userfiles/file/28165288335.pdfIn PDF document text
    • http://c-six.it/userfiles/files/foxurixexapixedizisugol.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/27965325733.pdfIn PDF document text
    • https://b2b-intelligence.it/uploads/file/9496953651.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/bijimubol.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/52463777849.pdfIn PDF document text
    • http://ibsdhc.hpds.work/ecdemo/web/js/ckfinder/files/files/jifozanotapojazatixomixer.pdfIn PDF document text
    • http://besteva.com/upload/files/relutekikutuloduwesalota.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/60755991090.pdfIn PDF document text
    • http://autokolcsonzoszolnok.hu/admin/fck_upload/file/gowivupiraji.pdfIn PDF document text
    • http://donovaly-ubytovanie-safran.sk/web/userfiles/file/gelagunemuwukemidegifulug.pdfIn PDF document text
    • https://valergences.fr/userfiles/file/xevosigo.pdfIn PDF document text
    • http://luberoff.com/userfiles/file/53526728439.pdfIn PDF document text
    • https://dijitalsanat.link/upload/files/solinukamaxulekefu.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161307ba2f15a8---zituzesuredem.pdfIn PDF document text
    • http://www.iciparis.ru/ckfinder/userfiles/files/44713208969.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/24701545996.pdfIn PDF document text
    • http://jolanyee.com/upload/files/202109041603225342.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/kukonewidobekigarobupe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=android+send+email+programmatically+without+intentPDF link annotation
    • 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_off0000f0a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A4 18508 bytes
SHA-256: 47f6ba1facd69540263b1e96e67fc85e7e38df407293516cc91c71fee96c62e7
font_01_sfnt_off00012154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12154 11240 bytes
SHA-256: e35e1127dd2fc2fd968a9defd6aff9199b979e210dcee286733219d68033293b
font_02_sfnt_off00013b5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1