Malicious PDF — malware analysis report

Static analysis result for SHA-256 822fb6ceaf26c8dc…

MALICIOUS

PDF

69.7 KB Created: 2021-09-18 21:07:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: cff2b746005570a62c83fa101ab178e8 SHA-1: cf1d1f8d4335a692009f8e81840563738b688aa1 SHA-256: 822fb6ceaf26c8dc7fea731e25463169a81b6c8e21352dff248831c38683c4c7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for these links. While no scripts were explicitly extracted, the nature of the embedded URLs and the ML detection point towards a phishing or malware distribution scheme.

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 http://dcbestwings.com/uploads/files/lanukuv.pdf In PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/voduvapem.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/24548945561.pdfIn PDF document text
    • http://geoass.eu/userfiles/files/tovotedogukew.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/luvagajejakebemotow.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/bobudakanino.pdfIn PDF document text
    • https://tour-paris-guide.com/cite_imgs/file/71819329096.pdfIn PDF document text
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/minozofebejixozigux.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/moxuz.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/xazewomarekesil.pdfIn PDF document text
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/80761015920.pdfIn PDF document text
    • http://sinojjacob.com/userfiles/file/74762725500.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/96548280968.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614123bd24b6f---pagenojikowezaraxakum.pdfIn PDF document text
    • http://inspiredindianfoundation.org/uploads/sulurikuzizanefujoj.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/161377bfa4eef1---68532411095.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/xeguxavoxavadoruwubek.pdfIn PDF document text
    • http://spc1991.com/ckfinder/userfiles/files/84192789391.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/toxebametuxejire.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/kekafejuxokakujiwarukin.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/xapozevugadidamozo.pdfIn PDF document text
    • http://chapraptti.org/userfiles/file/44903376009.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/94697255913.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/58594151980.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/69833353261.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=fifa+2007+ppssppPDF 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_off0000b5da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5DA 14592 bytes
SHA-256: cd1bb2c4d7aaddce1f4373ca0ff96f8e8a46219ec2b575e10497c39fce4441b2
font_01_sfnt_off0000da8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f2a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A4 10020 bytes
SHA-256: 347e3e984a2a44b1b38432c9f29b6d03010f5242f315113df13af75441949a07