Malicious PDF — malware analysis report

Static analysis result for SHA-256 16875ca9e18e94d0…

MALICIOUS

PDF

77.6 KB Created: 2021-10-10 11:26:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 02572888eaf1e77cbf59cd97be0000ee SHA-1: 8836a57e662155f36610d71274d89a2acb16dd9a SHA-256: 16875ca9e18e94d0f5c6150199abb45ec0e525d9e6c4aba6fe98efec49610a84
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the numerous unknown URLs suggest a phishing or redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to external sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://macauroommate.com/ckfinder/userfiles/files/rezanamunazitidan.pdf In PDF document text
    • http://gadkowski.pl/repository/filemanager/file/bavur.pdfIn PDF document text
    • http://ip-kamery.cz/files/file/93206039820.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161353d1400387---5729083403.pdfIn PDF document text
    • http://itcck.org/upload/editor/file/kutapufes.pdfIn PDF document text
    • http://haki.tincorner.com/uploads/files/sagesakoti.pdfIn PDF document text
    • http://manchetenewsms.com.br/ckfinder/userfiles/files/91967158652.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/6155c73dc2afd.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/33583756000.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/81465989407.pdfIn PDF document text
    • https://fruitssupplier.com/app/webroot/img/files/teborubimigukewiwowowav.pdfIn PDF document text
    • http://adm.stikom-db.ac.id/js/uploads/files/venizupajonametojiwetija.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1614536751d072---panabirojile.pdfIn PDF document text
    • http://grafitym.kz/files/file/totofakupaponatupitabovuw.pdfIn PDF document text
    • https://uzmanwebci.com/calisma2/files/uploads/71240992219.pdfIn PDF document text
    • https://webdatedepot.com/userfiles/file/8675310746.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/zudovepokexosiwifaganu.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/12630236137.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/fozekaxofaseraxu.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/67099396036.pdfIn PDF document text
    • http://kesifveotesi.com/files/14516878310.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dfff1ea449---78687701404.pdfIn PDF document text
    • https://gtsk.solar-napkollektor.hu/js/ckfinder/userfiles/files/jodajotirinugomelelu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=high+cholesterol+fish+to+avoidPDF 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_off0000c675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC675 10708 bytes
SHA-256: a12e158b1a710555b0c988c2ac3f4afe88a2f83a6150f8010550c3a4a4010233
font_01_sfnt_off0000def8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f70a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF70A 18952 bytes
SHA-256: 462c54129af70db8bbad55da84a997a74642efe45738e3fe072d12fc7cf01af8