Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b3b0962a571e97…

MALICIOUS

PDF

73.1 KB Created: 2021-09-12 12:55:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9dba70a56cd3e722b68fc3e2b29bc324 SHA-1: adbe70959f8c673ed2338c40ca455e12cea89655 SHA-256: 77b3b0962a571e9788bb8e9082cad19c6f3979528255ad9c11c492bc89b18d18
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs pointing to external domains, suggesting a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using many distinct, disposable domains to host content, further supporting a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://cructi.ru/uplcv?utm_term=download+nova+mod PDF link annotation
    • http://brenderup.ro/mm/file/ramonujelew.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/5127803009.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612feef6382f5---16779826179.pdfIn PDF document text
    • http://byty-pardubice.eu/UserFiles/File/nukebawujepadeguvola.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/gilimapifoteb.pdfIn PDF document text
    • http://th-hl.com///upload/files/mijezoviduxefixukifen.pdfIn PDF document text
    • http://xn--oy2b9bv81anouola.com/upload/file/202109061330226569.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/jarapovenufobabo.pdfIn PDF document text
    • http://packturf.fr/files/podak.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/15091438263.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c76433f975---20778793393.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/wesalomidizonaridudebi.pdfIn PDF document text
    • https://kiptep.ru/file/47051486294.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/76882631293.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/wawebipalujopanolo.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/fedunesoguwemogolerimad.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/xejurozorip.pdfIn PDF document text
    • https://newcar-rental.com/uploads/files/202109061335535903.pdfIn PDF document text
    • https://alev.az/userfiles/file/11016341663.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/65959059625.pdfIn PDF document text
    • http://papierplus.pl/userfiles/file/loligoju.pdfIn PDF document text
    • http://denda.co.kr/ckfinder/userfiles/files/51666705569.pdfIn PDF document text
    • http://ipmarketing.net/FCKeditor/editor/filemanager/connectors/userfiles/file/82123307848.pdfIn PDF document text
    • http://giaydantuongphongngudep.com/images/news/file/23783789681.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_off0000bbc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBC3 9972 bytes
SHA-256: 42c88ce20562177d39ab129c37c94e8f1d3531277a6cfe707509c8dc84ec1b4d
font_01_sfnt_off0000d1cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1CD 17532 bytes
SHA-256: 6a4202f45a60647b9b7b84e979e023f9876f519d1c98e7688971be0356f83d48
font_02_sfnt_off0000ff2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1