High Severity
Attachment: HTML smuggling 'body onload' with high entropy and suspicious text
Description
Potential HTML Smuggling. This rule inspects HTML attachments that contain "body unload", high entropy, and suspicious text.
References
No references.
Sublime Security
Created Sep 25th, 2023 • Last updated Sep 25th, 2023
Feed Source
Sublime Core Feed
Source
type.inbound
and any(attachments,
(
.file_extension in~ ("html", "htm", "shtml", "dhtml", "xhtml")
or (
.file_extension is null
and .file_type == "unknown"
and .content_type == "application/octet-stream"
)
or .file_extension in~ $file_extensions_common_archives
or .file_type == "html"
or .content_type == "text/html"
)
and any(file.explode(.),
.scan.entropy.entropy >= 5
and any(.scan.strings.strings, strings.ilike(., "*body onload*"))
and any(.scan.strings.strings, regex.icontains(., 'data:image/.*;base64'))
and any(.scan.strings.strings, strings.ilike(., "*document pass*"))
)
)
Playground
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