Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ab4f70528824a01…

MALICIOUS

PDF

81.8 KB Created: 2021-10-08 18:00:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ffdb30fae4cf64904c7c56bb3450004f SHA-1: 54e03abe1079b62a8ae2373b5484ebb1eb44c6f5 SHA-256: 8ab4f70528824a0100a1df1448ff67ea86bfc9553b1c66c79dd0f30ef985f483
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 malicious intent. The PDF contains a large number of embedded URLs pointing to various domains, suggesting a link farm designed to distribute malicious content or conduct phishing attacks. The presence of embedded JavaScript, though not fully analyzed due to obfuscation, further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://chcial.ru/uplcv?utm_term=a+to+z+new+words PDF link annotation
    • http://krasneclanky.cz/uploads/larabuvalirej.pdfIn PDF document text
    • http://greatnice.club/updatefiles/file/nuwizunometawomikab.pdfIn PDF document text
    • https://pkmoscow.ru/ckfinder/userfiles/files/39970624623.pdfIn PDF document text
    • https://rmp-familienanzeigen.de/cms/files/luwubilisuj.pdfIn PDF document text
    • http://swotaweb.com/img/upload/file/67475604933.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/18252077775.pdfIn PDF document text
    • http://fentesmakina.com/paket/upload/files/88556737789.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/medozorebodi.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/25627275412.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613bea6d97655---bokefijexuri.pdfIn PDF document text
    • http://thenext.pk/userfiles/files/nulud.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210906152017.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/gobiruruvukilanaduwulex.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/85899518825.pdfIn PDF document text
    • http://about-dogs.ru/upload/file/62387256976.pdfIn PDF document text
    • http://tko.wavedev.net/img/files/files/18436829852.pdfIn PDF document text
    • http://tizianaiberti.it/userfiles/files/togonobakigavelifiliti.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/eeu3cui1fotebbina72r7v6kfs/22877786123.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/5878402429.pdfIn PDF document text
    • http://dreamwith.gni.kr/ckupload/files/dafunada.pdfIn PDF document text
    • http://baheth24aqari.com/ckfinder/userfiles/files/62764615539.pdfIn PDF document text
    • http://flyingfish-stay.com/userfiles/file/tasuribupobavunuluvu.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/juvozizip.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/14751367517.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_off0000da8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8E 10068 bytes
SHA-256: afef73248eada2758ee107a64f3ba1688cbcbe984a7834ce5a893b6418d0b690
font_01_sfnt_off0000f13c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13C 18964 bytes
SHA-256: b6566e2dad0d5a144110a8d9b3c7c1486ecbe7ef148e8863717de95417b5b41f
font_02_sfnt_off000121a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1