Malicious PDF — malware analysis report

Static analysis result for SHA-256 f433ed925786d327…

MALICIOUS

PDF

75.4 KB Created: 2021-09-18 07:00:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f7f21f2b24bf2d830448cdd7bd2a2c13 SHA-1: 49913d92f0796332790f375f548d307eb37d4d96 SHA-256: f433ed925786d327d6d2b75a03d0865e69e548da14c7a490bc442cdcd9af9641
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is flagged as a link farm on disposable hosting, indicating a malicious intent to redirect users. The ML classifier and ClamAV detection strongly suggest this PDF is malicious, likely a phishing or malware distribution lure. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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.
  • 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://chcial.ru/uplcv?utm_term=live+wallpaper+for+my+phone PDF link annotation
    • http://harchovyk.com/userfiles/file/44274691533.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/6437988951.pdfIn PDF document text
    • http://360global.ca/userfiles/file/xabusudogudowogijozawifa.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/keloxalas.pdfIn PDF document text
    • https://jf-orvalho.pt/userfiles/file/74686857043.pdfIn PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/4227651390.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/wisavawopefo.pdfIn PDF document text
    • https://www.utn.ac.cr/sites/default/files/files/95539120950.pdfIn PDF document text
    • http://xahscw.com/userfiles/file/51555466697.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/zatoropoxujezepabopem.pdfIn PDF document text
    • http://hzqzg.com/d/files/98778329924.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/wokujogaponif.pdfIn PDF document text
    • https://elminhaj.org/userfiles/file/4511485226.pdfIn PDF document text
    • https://skillmapmagazine.com/ckfinder/userfiles/files/93875037173.pdfIn PDF document text
    • https://www.pelicanfinancialnetwork.com/ckfinder/userfiles/files/jiwupuduravexuwike.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/50384313221.pdfIn PDF document text
    • http://cesnek-vysocina.cz/UserFiles/File/3729206910.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/18948759782.pdfIn PDF document text
    • http://skupka54.ru/upload/m/jufuxokobodesoxaga.pdfIn PDF document text
    • http://hlqh.net/userfiles/file/20210902131949_1133106877.pdfIn PDF document text
    • https://best-label.com/upload/files/masimavisivepurobum.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/tusudafenasetagifiv.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/23376906879.pdfIn PDF document text
    • http://munnarteabungalows.com/userfiles/file/rojipagad.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/basidobawuseni.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_off0000c1ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1CA 10580 bytes
SHA-256: ab0a797a127cc8b9f343d41df7e71f81cda27653fd128066352b22f851188695
font_01_sfnt_off0000d9bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D1 17980 bytes
SHA-256: 7b1d58efb68d06678e3f880ae1291e9e95503b0dbb2ad6b1a9ca44998f178b23