Malicious PDF — malware analysis report

Static analysis result for SHA-256 e454efd80b67c541…

MALICIOUS

PDF

71.9 KB Created: 2021-10-07 08:53:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cec81d05382a2cc8b1c5ae122f60da2a SHA-1: 8ec7e442234569c01a29c981be1df1e50e339eee SHA-256: e454efd80b67c5413804d5344659490ed8fa098ad125f242c4e0eabd77fb9d6d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF sample was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The presence of numerous external URIs, many on disposable hosting and configured as a link farm, strongly suggests a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and URI patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://synerhu.ru/uplcv?utm_term=topology+and+geometry+pdf PDF link annotation
    • http://yilip.net/userData/board/file/15186712902.pdfIn PDF document text
    • http://vodova51-53.cz/files/51191552000.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/15923346510.pdfIn PDF document text
    • http://hydrogears.com/survey/userfiles/files/59676779504.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/zewebofazuj.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/marisuja.pdfIn PDF document text
    • http://flairpens.ru/uploads/files/funowitunodenulabira.pdfIn PDF document text
    • https://gelblighting.com/userfiles/files/xamufonirawebageninoxiduf.pdfIn PDF document text
    • http://maekuangudomthara.com/ckfinder/userfiles/files/86858368209.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/74259140531.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/nofexurujalepuvutonu.pdfIn PDF document text
    • http://bodybybodyology.com/ckfinder/userfiles/files/mupokizejatubazidojaji.pdfIn PDF document text
    • http://slsnn.ru/content/files/39044948968.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/kemiserezudekamuribavune.pdfIn PDF document text
    • https://mptradingcompany.com/userfiles/file/pojopisepoxejumotenof.pdfIn PDF document text
    • https://sportnazona.bg/f/uploads/files/wizuju.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/66384088723.pdfIn PDF document text
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/80550305107.pdfIn PDF document text
    • http://nasledie-sluck.by/var/upload/file/nidipamupezobatuxetox.pdfIn PDF document text
    • https://rgcsmt.org/ckfinder/userfiles/files/galakuduj.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fc4f63f0eb.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/9523056884.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/zunoriwusepazizoguzurezu.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/68787145754.pdfIn PDF document text
    • http://viettelhaiphong.me/data/dulieu/files/94039514335.pdfIn PDF document text
    • http://associatedreclaimed.com/userfiles/files/78775916961.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_off0000b8ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0DC 15868 bytes
SHA-256: fd8f249da69da24fd4e92aeb85349e31c5c98efa0790c4298dd4d2dc744b2601
font_02_sfnt_off0000f996.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF996 10660 bytes
SHA-256: 1b734bfb3aff9f930fe9b7527dd15a3f9fe3d8bb90395d4c6d2187f329957492