Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fd23cf775a48308…

MALICIOUS

PDF

68.1 KB Created: 2021-10-01 10:23:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 000b1c269c6262257eec3a88eb2ee075 SHA-1: f374712ddfe4a97ba58f2f315dccb49b7affa20f SHA-256: 4fd23cf775a48308f6625119b52549c62669cd8a426538172f5b23af7a7f7058
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farms pointing to various domains, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. While no scripts were explicitly extracted, the structure and heuristic firings suggest a malicious document designed to lure users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • 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://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613adc225cedd---rolasimefiwesun.pdf In PDF document text
    • https://beautifulhairstore.com/upload/files/20672869618.pdfIn PDF document text
    • http://nhac.ditimchanly.org/Images_upload/files/36364891011.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/97670965671.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/bexiwipel.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/d046d925b4a7a985586fefcde2671e41/xobekodumivumukijapu.pdfIn PDF document text
    • https://mytshirtcreator.com/app/webroot/files/file/ruzubonigujurupepe.pdfIn PDF document text
    • https://curvy.tw/upload/files/jurokafiwodoriturujigu.pdfIn PDF document text
    • http://sgrdpandher.com/userfiles/file/zuputure.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/64652270c19bf5d912a3cf6b403ed928/tosotexisexorevebet.pdfIn PDF document text
    • http://rmgoals.com/userfiles/files/sirorenofopupifalikota.pdfIn PDF document text
    • http://immobilieninvestors.net/userfiles/file/gugodamebedimilefijexurib.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/mirisuga.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613553ae15f21---751423691.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614c01beb04ab---tevira.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/fetebitepebumamanewiguw.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/volefuzibanamol.pdfIn PDF document text
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/25251840216.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/39767751660.pdfIn PDF document text
    • http://jgbt.us/pds/userfiles/files/8031487930.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=clash+of+war+mod+apkPDF 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_off0000ac86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC86 10544 bytes
SHA-256: c8a46690a56051816077a23aec4db32cf4e21cc53b6b81ac51617d42e9a4ff81
font_01_sfnt_off0000c49e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC49E 15432 bytes
SHA-256: 620a008544c08ba73636b12f54e61070e077b36ea65bd2106f973dc3429abc16
font_02_sfnt_off0000ebad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1