Malicious PDF — malware analysis report

Static analysis result for SHA-256 1238c10511cb8342…

MALICIOUS

PDF

82.3 KB Created: 2021-09-13 08:03:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5d4003c0fd1661fe9c560e5ec8ca32ad SHA-1: 6b8afa70fe25264072e25affe66901ce0feb83af SHA-256: 1238c10511cb8342f7fe76c148b342827a52bcd0082206a2cf86096b509995d6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links, common in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.southdownscellars.co.uk/ckfinder/userfiles/files/75371478403.pdf In PDF document text
    • http://msinziniering.com/userfiles/file/nezavavusawimo.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/71161598884.pdfIn PDF document text
    • http://huijingweb.com/upload_fck/file/2021-9-3/20210903125112211908.pdfIn PDF document text
    • http://thuexe7cho.vn/upload/files/valaxawibutojuxafojuzimem.pdfIn PDF document text
    • http://kovospm.cz/fotky/file/nepexijaxubofiginaxapa.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/54991321015.pdfIn PDF document text
    • http://davobio.com/upload/files/83639690248.pdfIn PDF document text
    • http://youil.org/userData/board/file/33342583960.pdfIn PDF document text
    • https://anandamsanyal.com/userfiles/file/jexan.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/lokomevatuzex.pdfIn PDF document text
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/ludalupovigepovolapidom.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/113c30c926de94d0b7498004fcf6499d/55224130027.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/vifuzetekomamu.pdfIn PDF document text
    • http://fmmvn.net/userfiles/files/vopikisevadenarosipimo.pdfIn PDF document text
    • http://hpcad.pl/Upload/file/mirogedijevotefogun.pdfIn PDF document text
    • https://mmszke.hu/files/file/dagupigarivabepan.pdfIn PDF document text
    • http://elitakhealing.com/ckfinder/userfiles/files/68992752248.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/mipabixesado.pdfIn PDF document text
    • https://elsadaulte.com/ckfinder/userfiles/files/nokotikarafuxumaleg.pdfIn PDF document text
    • http://szybkieprawko.pl/szybkieprawko.pl/user/admin/fck/file/vosapurikuk.pdfIn PDF document text
    • http://mijn-nederland.nl/userfiles/file/4718736198.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/vefodupufipe.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/eeb688a91122387927c0a08192132a8b/80922824552.pdfIn PDF document text
    • https://traicaygiasi.com/Images_upload/files/jugovamajikijir.pdfIn PDF document text
    • http://cherryontop.pl/upload/fotki/file/16981468351.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=aankhen+old+movie+songsPDF 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_off0000dc7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC7E 10636 bytes
SHA-256: 989818b3253eb8f45868f07fe4eaad534c8e7dac79f1e43b70da0a76ad98f128
font_01_sfnt_off0000f468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF468 18020 bytes
SHA-256: 68eadcba057f93454193c53389469ab915ef2b5181a0890c2b0fd2e574e3eb2e
font_02_sfnt_off0001233c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1233C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1