Malicious PDF — malware analysis report

Static analysis result for SHA-256 df9ea28abdeb2e61…

MALICIOUS

PDF

91.9 KB Created: 2021-09-18 16:13:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 967954f49b269f114deb8c2f87094129 SHA-1: ea18c2f858031733768420bcf8ae7f055c594694 SHA-256: df9ea28abdeb2e6162175dba89f15db4d50326d02acc16ec13a8714d6b9f75d8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with numerous external URIs, many hosted on disposable domains, suggesting an attempt to distribute malicious content or phish for credentials. Although no scripts were explicitly extracted, the PDF structure and embedded URIs point towards a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://www.mediawerf.nl/bundles/store24backoffice/ckfinder/userfiles/files/79400166613.pdf In PDF document text
    • http://luckysim.com/userfiles/file/62410922193.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/sazegabadibud.pdfIn PDF document text
    • https://ssekolkata.com/ckfinder/userfiles/files/zumokekewux.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/10307185154.pdfIn PDF document text
    • http://sumisaedu.com/FileData/ckfinder/files/20210914_13B667065E156815.pdfIn PDF document text
    • https://andrejc.si/files/file/4768719730.pdfIn PDF document text
    • https://bestrecycledautoparts.net/images_i/file/66650539458.pdfIn PDF document text
    • http://www.sanjuktabanerjee.com/fckimages/file/52598973520.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/wekigolitorawovekaki.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d333e4d223---pavulawosuvu.pdfIn PDF document text
    • https://moulindelarroque.com/userfiles/file/wetesubiverusuwegujugiw.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/boxuviwikubojatipu.pdfIn PDF document text
    • http://synphabase.ch/upload/file/vasubonejogif.pdfIn PDF document text
    • http://www.hkrns.org.hk/ckfinder/userfiles/files/61595950371.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/85548241274.pdfIn PDF document text
    • http://baocaosuhoatoc.com/luutru/files/46191584361.pdfIn PDF document text
    • http://adacu.org/userfiles/file/20210916102237.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/68948954037.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/15676957834.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/tivepal.pdfIn PDF document text
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/46737063530.pdfIn PDF document text
    • https://hgindustrial.eu/userfiles/files/bedesefudofo.pdfIn PDF document text
    • http://fields-on-earth.com/images/blog/file/lazasomega.pdfIn PDF document text
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/27170260697.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=best+keyword+rank+checker+toolPDF 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_off00010468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10468 17320 bytes
SHA-256: 15e28e776e73244e9ba5046b1fd51bc3347a7aa9f1d8df78e0c9eba51643e11d
font_01_sfnt_off00013144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13144 10720 bytes
SHA-256: dfd89260ae1bdd39a04964c08eb75f847abc4c5ef2a7b26f33be0aa96de3ecbb
font_02_sfnt_off000149ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1