Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad78cedf4eaa5e76…

MALICIOUS

PDF

68.3 KB Created: 2021-10-01 19:27:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 6ba9041b1efcbd6d5350057a3aa7a637 SHA-1: 267385ee2849de4f5fc918aabe9fd88b1c33d84b SHA-256: ad78cedf4eaa5e761e891314548252e5c35e14b3bd8a07d57ddecdb082cdeee0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. 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 to potentially malicious content. The presence of external URIs and the overall structure suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://krisoc.ru/uplcv?utm_term=elective+biology+textbook+pdf PDF link annotation
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/jiragopomebamer.pdfIn PDF document text
    • http://globalsocialwlefaresummit.com/app/webroot/uploads/ckuploads/files/70659929360.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/161487692a4766---3816312704.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/xozowe.pdfIn PDF document text
    • http://imapbook.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/vuxinuperit.pdfIn PDF document text
    • http://nofatrans-int.com/userfiles/file/26576428353.pdfIn PDF document text
    • http://atomicattack.com/atomic/fckimages/file/gotivosomusawo.pdfIn PDF document text
    • https://i-try.tw/upfile/files/2021/09/15/99528486741.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/37076643340.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/b6c5c9811266e0df0af1abf4f63fbcd3/roligupomem.pdfIn PDF document text
    • http://ck-buhgalter.ru/userfiles/file/21282824034.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/20355788769.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/95536942468.pdfIn PDF document text
    • https://cedria.es/DOCUMENTS/FotosFCKEditor/file/tivugijefegego.pdfIn PDF document text
    • http://controlsystemco.com/cache/fck_files/file/29843835634.pdfIn PDF document text
    • http://yey.uw52.com/upload/files/wiwezekerudoxolaru.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/paxiwamobuluzevilulet.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/naxoputegur.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/wizuvusebapuvekopifagina.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/xexofitetokowubuz.pdfIn PDF document text
    • https://pastijptoto.com/contents/files/37450424624.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/30013664544.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/35303273289.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/19350520042.pdfIn PDF document text
    • 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_off0000ae4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE4E 10760 bytes
SHA-256: 66a86a8300e2d23c5a33c0f73c322288e7feea4496ccec5a1a68ab11749b9237
font_01_sfnt_off0000c6c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C2 15096 bytes
SHA-256: 6e07b98f5f50d540c06805cb8f5e07c5b11a99005d8a3cef9b7f9850cc0762ec
font_02_sfnt_off0000eb82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1