Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b613d60b901ca65…

MALICIOUS

PDF

78.2 KB Created: 2021-09-16 04:31:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e4b1e482b53dc9acd1791eef7e246605 SHA-1: 8b1674903a2b51d5320217fa64b4d2c024f0605b SHA-256: 6b613d60b901ca6500f2b851721337cba5b7eb63d2df2bd0ac4aecc4e8aa753f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution by directing users to external sites. The embedded JavaScript is likely used to obfuscate the malicious links or perform further actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://oniceh.ru/uplcv?utm_term=free+v+bucks+xyz
    • http://kingsauto-bar.com/js/upload/files/nuzufetu.pdf
    • http://www.vandiestbrandstoffen.be/uploads/files/vazunabo.pdf
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/sitifexerujuz.pdf
    • http://aluminial.pnh.pt/js/ckfinder/userfiles/files/sefimiwos.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370f77ba79b---42404628513.pdf
    • http://go-forum.cn/upload/files/gifadajamotewotabuzakanoz.pdf
    • https://motodubai.com/uploaded_images/files/mejopigesopo.pdf
    • http://www.cpiequipos.com/assets/images/user_files/files/fuwujekutosopejegagokavil.pdf
    • http://www.jindatunnel.com/up_files/file/meteji.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/eq2h0g5tfbnmfhn9ok73tp1l75/47004203408.pdf
    • https://bvphcn.bdata.vn/upload/files/85933159127.pdf
    • http://teknis.it/userfiles/files/64105636572.pdf
    • http://invismortgagebroker.com/images/file/21702842782.pdf
    • http://diakmelo.hu/ckfinder/userfiles/files/5872698154.pdf
    • http://hocikto.info/userfiles/file/90881090990.pdf
    • http://jar-ted.pl/file/vujixukitifuzenigiwofexi.pdf
    • http://konferencii.org/web/uploads/assets/file/84925080926.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613faa731bc3b---jezesaxeb.pdf
    • http://carlaschroyen.com/content_docs/zexemavaluzewibediga.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6cc30a77b---37244724395.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/161302320a845f---4511972918.pdf
    • http://minuspk.ru/minuspk.ru/userfiles/file/53419632833.pdf
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/tagewiweb.pdf
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/77631737786.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b618.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB618 16792 bytes
font_01_sfnt_off0000ce2a.bin
9689573edb5f8fcc2780806b8c33bc93142987b36e6c367798d8b1f6dd472900
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE2A 18476 bytes
font_02_sfnt_off0000fda3.bin
fddcbe21bdf9fb2753729b4ab5b26d7a3fbb01e3fe51d41ab0725360e25c189d
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA3 16244 bytes
font_03_sfnt_off00011392.bin
17f0680102396b6ff0ee0e836969a02114964ce596bb545bb9434ec30819e43a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11392 10252 bytes