Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc8de248edd83708…

MALICIOUS

PDF

82.4 KB Created: 2021-09-12 16:50:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e166dab7499fe525398081a61520dfb9 SHA-1: 4e91a68cf219afca94291decf234d470f04642f6 SHA-256: bc8de248edd83708165f0d4bb3b5bce5a54fdf84c8e2be10d43fe31c53b536d6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct domains, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics point towards a malicious document designed to redirect users to external, potentially harmful, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://insolite.lu/img/userfiles/files/24482172068.pdf In PDF document text
    • http://nbc.ua/design/pic/file/pifopozolilipen.pdfIn PDF document text
    • http://outspokenholland.com/userfiles/fckFile/20210911092457.pdfIn PDF document text
    • http://hb-hospital.com/file_upload/fck_upfile/file/zuxozegivefavazimodewip.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/52af84c6a0fec68c1bcbead8215c62f8/xusobexuziwa.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210912080213.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/93145100800.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/51063893019.pdfIn PDF document text
    • https://chasehr.in/userfiles/file/rugad.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/kupilisavus.pdfIn PDF document text
    • http://cmtdental.com/upload/ckimg/files/95652911824.pdfIn PDF document text
    • https://badanie-wody.pl/galeria/file/30030810976.pdfIn PDF document text
    • http://one9five.com/userfiles/files/jazureluvetewurave.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/97788207488.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/66006814346.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/kapuvuvavobasak.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/2650043776d33b524c2e352653bd507b/kazekawesixofasuwom.pdfIn PDF document text
    • http://zeminyerkaplama.com/upload/ckfinder/files/vemozasirifali.pdfIn PDF document text
    • http://dgjinhak.kr/DATA/upload/files/202109110623164871.pdfIn PDF document text
    • http://frankifoto.com/uploads/pages/files/zijujir.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/72738226292.pdfIn PDF document text
    • https://vieclamlaocai.vn/webroot/img/files/fepufebonazetugu.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/resajazatepoxidexopireno.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=best+hd+streaming+websitesPDF 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_off0000dec6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC6 10808 bytes
SHA-256: 42d90746b4bb39e95360f58122c3a081e790e37617c8088751cf7479f8700b71
font_01_sfnt_off0000f75e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75E 17304 bytes
SHA-256: 62f0183ae914023c659606468eedc00df270b3ac27745cac693801634bcdc364
font_02_sfnt_off000123c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1