Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c600b8440d9ae4b…

MALICIOUS

PDF

70.1 KB Created: 2021-09-20 17:02:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1d289d7a8ec28526e92df9c4210f9001 SHA-1: 5b9029259e31e643c2eb3f39adb438247231e1e1 SHA-256: 8c600b8440d9ae4b04aaaeaacee5b0374a619c809d79988bc0b645f70fa3adf4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or malware distribution attempt. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links on disposable domains, likely to redirect users to malicious sites. The presence of embedded URLs, including one with 'utm_term=insta+private+viewer', points to a social engineering lure to trick users into clicking through to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://nichecnk.leaddeehub.com/userfiles/files/60490315135.pdf In PDF document text
    • https://imagebrandstudio.com/userfiles/file/41113383222.pdfIn PDF document text
    • http://www.vako.vn/app/webroot/uploads/files/zekogamaxemara.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/gerotofev.pdfIn PDF document text
    • http://decorstore.eu/upload/file/kirikoguludafiwaluzusofis.pdfIn PDF document text
    • http://altus.pl/userfiles/file/kifoteli.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/69867414869.pdfIn PDF document text
    • http://nataliashishkina.com/userfiles/file/lanujep.pdfIn PDF document text
    • https://gikguamerica.com/userfiles/file/lowekarukisagalezewik.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/jogisimakafagujubiki.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/2461217401.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/zenurogewuto.pdfIn PDF document text
    • https://hlj-vibration.com/uploads/image/20210902/files/20210902130351.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16142eec352e44---tuvadojesijavo.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16130670944125---90241781785.pdfIn PDF document text
    • http://www.swaving-stalinrichting.nl/ckfinder/userfiles/files/7666812780.pdfIn PDF document text
    • http://dongbanja.com/userData/ebizro_board/file/nemuxava.pdfIn PDF document text
    • http://ladyvenus.it/userfiles/files/gufak.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/jofetawewupekudorifa.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///nurotejuvoporeveto.pdfIn PDF document text
    • https://eprobatdz.com/ckfinder/userfiles/files/15039211218.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/66566565677.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/wumirerigemukezesuriku.pdfIn PDF document text
    • http://sun-green.eu/ckfinder/userfiles/files/22282769378.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=insta+private+viewerPDF 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_off0000b388.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB388 10180 bytes
SHA-256: 23ab060d2abf6998fc33f00e91ee6e9c675bdf850f56faa50adea3738adea4e2
font_01_sfnt_off0000ca86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE298 16112 bytes
SHA-256: 785aadaed656c6d3dfc4f3e30ac2b78b770f28f034ce593ae57ac3c81c2f8eb8