Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fb79bf2296f4558…

MALICIOUS

PDF

84.6 KB Created: 2021-09-16 11:29:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b6caf754fbf4023156dd9d5f53d8eaca SHA-1: 287ab9abe5e0eb835a61fee985ef80f9494c8e11 SHA-256: 3fb79bf2296f4558a7fabec8d18e96333b8c90ac020ba8632a28f751fcf7ffc1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to suspicious domains, and is flagged by heuristics as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the structure and URL patterns suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://needychild.org/ckfinder/userfiles/files/fivanagujinufefo.pdf In PDF document text
    • https://karapinler.com/calisma2/files/uploads/duvipipitagugusikedazipew.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/54848271550.pdfIn PDF document text
    • http://tajeer.co/userfiles/file/tawuxomokomotudufot.pdfIn PDF document text
    • http://gugugroup.com/userfiles/texebivilizodoropesekav.pdfIn PDF document text
    • http://robertfeinberglaw.com/images/edit_images/file/gukerisi.pdfIn PDF document text
    • http://www.moyekolodin.com/files/lajubufapajuvo.pdfIn PDF document text
    • https://learnrkb.jugalbandiresearch.com/ckfinder/userfiles/files/28856074746.pdfIn PDF document text
    • http://aurora-c.jp/files/files/63778985845.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c1998575a---xirotine.pdfIn PDF document text
    • http://duocmyphamcongty.com/app/webroot/uploads/files/gejalikikalopefavodip.pdfIn PDF document text
    • http://skiflogistics.ru/userfiles/file/sotofexurijure.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/vulijoduzusapo.pdfIn PDF document text
    • http://sowa-architekci.pl/userfiles/files/8086559356.pdfIn PDF document text
    • http://www.heksan.com.pl/file/fagugexirivusufuk.pdfIn PDF document text
    • http://tianlanip.com/filespath/files/20210911090142.pdfIn PDF document text
    • https://xeroxexpres.cz/userfiles/file/jujotopikosazonuz.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/ruminisurepuvoxujelufi.pdfIn PDF document text
    • https://svetplus.com/userfiles/files/28069555764.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/pokiduditotazenes.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/patepejupewoz.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/meradaxilaxa.pdfIn PDF document text
    • https://karaari.leaddeehub.com/userfiles/files/41800566294.pdfIn PDF document text
    • https://jetaime-shop.dvsportbg.com/files/3547561435.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=iphone+beter+dan+androidPDF 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_off0000e760.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE760 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ff77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF77 10368 bytes
SHA-256: b202f54b8c51dbe1eb38f156892e407dde426616386a34f61af375d5f10c919a
font_02_sfnt_off00011686.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11686 17920 bytes
SHA-256: 8697c9e8124dfce7d9e439a2999eb69b546f693fe5556c5f1eba3646f67e1230