Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3518e65ed454adb…

MALICIOUS

PDF

84.5 KB Created: 2021-10-05 20:06:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 36de154cb2d22a3a3cd4636106e2de9e SHA-1: 3c00367407c36004188781db72e22e13a26c03c2 SHA-256: c3518e65ed454adb2d0ca4fc797f85271e5e8a3f20e3a862efb70b0fcdfe9489
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm designed to redirect users. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a malicious intent to redirect users to potentially harmful sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://huntic.ru/uplcv?utm_term=nvivo+free+for+students
    • http://niktid.ru/userfiles/file/3148761100.pdf
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/mikatamuwufi.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614639d3e4c61---36131102956.pdf
    • https://kochitaxirental.com/ckfinder/userfiles/files/21642170848.pdf
    • http://tiramisu-o.com/yamituki-n/uploads/files/30307896351.pdf
    • http://synthecinter.com/userfiles/files/5127138634.pdf
    • https://sportnazona.bg/f/uploads/files/rirenax.pdf
    • https://diedacorporation.net/freesiafiles/file/82394378959.pdf
    • http://inlovehuahin.com/file_media/file_image/file/84291007878.pdf
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/82896411036.pdf
    • https://livermore.com/wysiwygfiles/file/85997529548.pdf
    • https://alpinashop.bg/files/26970529354.pdf
    • http://ahdjcm.com/upload/files/29396494197.pdf
    • http://oticonshop.com/ckfinder/userfiles/files/nobigazutevigoxonevefam.pdf
    • http://naplesredeals.com/userfiles/files/vuzemupobaj.pdf
    • http://pastadimatteo.com/ckfinder/userfiles/files/57698038462.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b1de7e34b---kejuvilumixujesa.pdf
    • http://lifecontinues.ru/images/files/mozesazilono.pdf
    • https://simondaulte.com/ckfinder/userfiles/files/pitirudidedazadipanij.pdf
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/52997548098.pdf
    • http://klhl.com/userfiles/file/kutewavegoxufojikapopujor.pdf
    • https://komunalno-vrgorac.hr/files/zubulipukaru.pdf
    • http://bellamy.tw/uploads/files/202109050357569014.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e027.bin
7dd631d691bfd0ffb7dff77212c920a6ebf58e40ae295ec17f94edcc28aa6437
pdf-font-stream PDF embedded font (sfnt) at offset 0xE027 10284 bytes
font_01_sfnt_off0000f779.bin
06948e5030c9b108d07490ba39eae24d9e23db4af19c5de26d1add70ff657bf1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF779 19356 bytes
font_02_sfnt_off00012aa8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12AA8 16792 bytes