Malicious PDF — malware analysis report

Static analysis result for SHA-256 86c5dd6da6439fa8…

MALICIOUS

PDF

85.2 KB Created: 2021-09-15 15:32:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2e4f96b0f5a464b47ad1f3576f48abcd SHA-1: 96eae54cd51f2451694f9ccc104c6f220e371bef SHA-256: 86c5dd6da6439fa81f8fe9b3051f81e1a8722b86b313947aae71735016a1aa47
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. The PDF contains numerous embedded URLs pointing to various domains, suggesting an attempt to redirect users to potentially malicious websites. While no scripts were directly extracted, the PDF structure and the presence of external URIs are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://faktxeber.com/resimler/files/virixusegeribewewuf.pdf In PDF document text
    • http://resortcrimea.com/ckfinder/userfiles/files/wewuzavorenoxan.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/9598934749.pdfIn PDF document text
    • http://lagrupacio.cat/file/88153397797.pdfIn PDF document text
    • https://turkeyinsurance.info/images/file/livijatutoxuki.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/51048244454.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/91387348302.pdfIn PDF document text
    • https://ms01bet.com/contents/files/luwazavor.pdfIn PDF document text
    • https://girl0229960192.com/upload/users/files/vimokurasubezi.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/49247772883.pdfIn PDF document text
    • https://gegeny.hu/uploads/file/33438267142.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/83568157453.pdfIn PDF document text
    • http://vp-dmsh.ru/admin/ckfinder/userfiles/files/vuzide.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/banukomemukenobupusufam.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/mefonafimivizepusiw.pdfIn PDF document text
    • http://xn--zb0bw3kv4s8mn.com/upload/fckeditor/file/sitokevadanimifapunemoxus.pdfIn PDF document text
    • https://mldom.xyz/web/img/podborky/files/zadesomijogixu.pdfIn PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/7841493201.pdfIn PDF document text
    • https://equinox-e.com/upload/files/fumumofasizelitoz.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/53942499836.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613755b14e155---16703003377.pdfIn PDF document text
    • http://deurenhanger.nl/userfiles/file/bejaxamol.pdfIn PDF document text
    • http://caudafotografia.com/userfiles/files/vojujewuxako.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=sperm+wars+robin+baker+pdfPDF 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_off0000e542.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE542 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD59 10908 bytes
SHA-256: 25f8d54a74b377056cdd78ffd590b1bc509468f2040f56fd6c8275b11417ef06
font_02_sfnt_off00011659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11659 18516 bytes
SHA-256: be0725b43e8df7b73f2dcaf2b095f020d9b7e88d6663b76320a1ed9ffbf6e24a