Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f57c289b98f25a0…

MALICIOUS

PDF

76.3 KB Created: 2021-09-21 10:57:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c9ba31ce7091f9029db6b071b6cab259 SHA-1: f2c162801b13bc9658a3b9b22eb016197dd5989f SHA-256: 4f57c289b98f25a0eb8ff0f37d39373959ad87ff3d8d25b8ff9e0ec0be86e5da
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable domains, consistent with a link farm used for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://garmaclima.com/uploads/ckfinder/files/35669186003.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d85235942c---71423731694.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-7/20210907070601671453.pdfIn PDF document text
    • http://synerfreight.com/syner_upload/images/files/nigizamavusawenuwixevaxug.pdfIn PDF document text
    • http://drprdesaihospital.com/uploads/jegurajeseraxiros.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/61510683273.pdfIn PDF document text
    • https://livewireeventz.com/userfiles/file/12531692209.pdfIn PDF document text
    • http://teenmag.cz/userfiles/file/fejofasasogebivi.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613aad1727df2---31408630495.pdfIn PDF document text
    • http://blueview.nl/app/webroot/files/userfiles/files/57891233275.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1630444385.pdfIn PDF document text
    • https://sapporopools.com/contents/files/kixokufumexafusosix.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/naregitu.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/nilinivixigubum.pdfIn PDF document text
    • http://dongphat.net/upload/files/21290886903.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/77534493095.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/veguvolifadowe.pdfIn PDF document text
    • http://karpatskiles.ru/store/files/1536588372.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/74898746955.pdfIn PDF document text
    • http://z-i-f.ru/userfiles/file/keniz.pdfIn PDF document text
    • https://webaprint.be/img/file/40346459095.pdfIn PDF document text
    • http://sacoorhealth.pt/site/upload/file/wadejonaxexagevejo.pdfIn PDF document text
    • https://educhina.mn/editor/files/janilit.pdfIn PDF document text
    • http://resurrection-life.net/userfiles/files/liwupimerozixasurusunoxun.pdfIn PDF document text
    • http://montpellier-businessplan.eu/mbp/upload/images/images/upload/ckfinder/2335762949.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=app+to+watch+anime+without+adsPDF 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_off0000c6d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dee7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEE7 10800 bytes
SHA-256: 49f622d4345bd08f2e4feae0dd48575d4648007dee576e50154e7bbb5542776b
font_02_sfnt_off0000f7b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B3 17104 bytes
SHA-256: 0bfc4265ed2d345c3e088b1baab9e95281b4567347b970a76146eced49e5df65