CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
EPSS
Percentile
47.1%
Using carefully crafted input, an attacker may be able to sneak arbitrary HTML and CSS through Sanitize >= 3.0.0, < 6.0.2
when Sanitize is configured to use the built-in “relaxed” config or when using a custom config that allows style
elements and one or more CSS at-rules. This could result in XSS (cross-site scripting) or other undesired behavior when the malicious HTML and CSS are rendered in a browser.
Sanitize >= 6.0.2
performs additional escaping of CSS in style
element content, which fixes this issue.
Users who are unable to upgrade can prevent this issue by using a Sanitize config that doesn’t allow style
elements, using a Sanitize config that doesn’t allow CSS at-rules, or by manually escaping the character sequence </
as <\/
in style
element content.
This issue was found by @cure53 during an audit of a project that uses Sanitize and was reported by one of that project’s maintainers. Thank you!
github.com/rgrove/sanitize
github.com/rgrove/sanitize/commit/76ed46e6dc70820f38efe27de8dabd54dddb5220
github.com/rgrove/sanitize/releases/tag/v6.0.2
github.com/rgrove/sanitize/security/advisories/GHSA-f5ww-cq3m-q3g7
github.com/rubysec/ruby-advisory-db/blob/master/gems/sanitize/CVE-2023-36823.yml
lists.debian.org/debian-lts-announce/2023/11/msg00008.html
nvd.nist.gov/vuln/detail/CVE-2023-36823