Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8921e3846b0e297…

MALICIOUS

PDF

80.2 KB Created: 2021-09-12 02:52:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1400a2c62cc7fc73b13138c398212791 SHA-1: c1cc9a07368f2796566754a1f4b1ca0538570037 SHA-256: c8921e3846b0e2970b6f9c2d7bd79b3102d34d74668941e2fe92aa565e584a17
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it's a password-protected archive lure and a link farm. The presence of multiple disposable URLs suggests an attempt to distribute malicious content, likely a second-stage payload, under the guise of legitimate-looking files. No scripts were extracted, but the overall pattern points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 http://cuanhuaabshanquoc.vn/files/85725248550.pdf In PDF document text
    • https://mollis.rs/files/88955950484.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/97548610968.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/65140114122.pdfIn PDF document text
    • https://conviviodihera.it/dati/upload/file/zerilimis.pdfIn PDF document text
    • http://bibliotekaludwin.pl/img/upload/files/11273003489.pdfIn PDF document text
    • https://stayinbranson.com/ckfinder/triplebuserfiles/file/posugo.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/dasepulafozomukidava.pdfIn PDF document text
    • http://ciccioinpentola.com/userfiles/files/xizoziges.pdfIn PDF document text
    • http://parfumerieindex.nl/images/uploads/24677087254.pdfIn PDF document text
    • https://butterfly-propertymanagement.com/userfiles/file/54420125964.pdfIn PDF document text
    • http://koreabulk.net/userData/board/file/xumibetodeguzoresodasan.pdfIn PDF document text
    • http://exim5.hu/_user/file/magozemefuve.pdfIn PDF document text
    • http://mengnuanua.com/app/webroot/files/files/453109515.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/98275405092.pdfIn PDF document text
    • https://nurdagihaber.com/resimler/files/3867427688.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/bupaxef.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139c695a804b---26914643756.pdfIn PDF document text
    • http://sieuthibongda.net/ckfinder/userfiles/files/vajupofuliwow.pdfIn PDF document text
    • http://simpelms.nl/userfiles/files/51291400549.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/vazivudadejikulezatumifir.pdfIn PDF document text
    • https://gadesign52.com/uploads/files/202109050231471870.pdfIn PDF document text
    • http://msiutilities.biz/documents/43720422654.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/25987370991.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/96986577106.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/tejijum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=macbook+pro+hanging+on+startupPDF 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_off0000d749.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD749 10800 bytes
SHA-256: ded6b2b4b19ad45839a2ac557b7020dc8964512be3398648b010c62c85bddbb8
font_01_sfnt_off0000eff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF6 16444 bytes
SHA-256: 6faf6ea99cf44bc6bf215c08c0a22b1d94c1c2b5415b1848fc5267f044f90406
font_02_sfnt_off00011aa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1