Malicious PDF — malware analysis report

Static analysis result for SHA-256 848c640b17ecc4cd…

MALICIOUS

PDF

81.3 KB Created: 2021-09-09 01:53:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d74c60656cc2f1d755eaa3fa7fd159f8 SHA-1: c83d37701aaf538dc8134c7f1226bb709f5b7dac SHA-256: 848c640b17ecc4cd33e91e0d003eee93b3602975c6d34bd752de823f73f89ec6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically points to the use of numerous distinct, low-reputation hosts to obscure the true malicious destination.

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 https://oniceh.ru/uplcv?utm_term=nba+supercard+download PDF link annotation
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/92577893350.pdfIn PDF document text
    • http://mentor-tutor.com/newGroserLikeProject/uploads/files/81415062092.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16137e874eb8de---wuvovadiwibuxogevomon.pdfIn PDF document text
    • https://hijaulumut.com/contents/files/5956075238.pdfIn PDF document text
    • http://iccjsc.vn/images/uploads/files/23940120040.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6d7e8e3cbb4f3314b24d0e2410aab280/64506877224.pdfIn PDF document text
    • https://v-rshine.com/upload/images/files/74574556448.pdfIn PDF document text
    • http://dedanskecasinoer.dk/userfiles/file/9446413584.pdfIn PDF document text
    • http://netmutum.com/userfiles/file/budosu.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/57085575036.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/puvaf.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/22084121472.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/8243991455.pdfIn PDF document text
    • https://mysilo.com/upload/ckfinder/files/34602486188.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/52990072994.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/96464897434.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/fedekisojanazaxe.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/161354d583287e---reronufesugisevuxoxet.pdfIn PDF document text
    • http://samocvet.org/foto/ck/files/48660309058.pdfIn PDF document text
    • http://archetipoingegneria.it/userfiles/files/57685922782.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/wikigesuti.pdfIn PDF document text
    • https://hgb.se/filer/file/zibegawexodi.pdfIn PDF document text
    • http://hoclaixebinhthuan.com/upload/contentFile/file/72030325001.pdfIn PDF document text
    • http://mmckno2010.zkosuchdol.info/files/berunijovaloveroritobu.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_off0000d9b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B2 10620 bytes
SHA-256: 9249113876517779099560f142245de88c707d5c8e629c757e86e9dec011dd4b
font_01_sfnt_off0000f1f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A08 17540 bytes
SHA-256: 89c4d08f8d8201ecc41e8699b2794d0eb59c11a5c7cd1f1fa5da1d035d577dd1