Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-68747— CSS sanitizer allowlist bypass in html_sanitize_ex via non-declaration input

Quick assessment

Affected
rrrene html_sanitize_ex
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

WordPress Formidable Forms是WordPress基金会开源的一款表单创建插件。 René Föhring HtmlSanitizeEx 0.3.1版本至1.5.4之前版本存在输入验证错误漏洞，该漏洞源于CSS scrubber对输出中特殊元素的中和不当，未检查不匹配属性值声明模式的输入，允许未经身份验证的远程攻击者将CSS at-rules（包括导入远程样式表）注入到提供给其他用户的页面中。

CVSS 2.3 · Low EPSS 0.45% · P38

Affected Version Matrix 3

VendorProduct Version RangeStatus
rrrene html_sanitize_ex 0.3.1< 1.4.5 affected
1.5.0-rc.0< 1.5.4 affected
21f90012eb21aa36f4e3701b7547e12faf0f3c8b< * affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-68747

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
CSS sanitizer allowlist bypass in html_sanitize_ex via non-declaration input
Source: CVE Program / CVE List V5
Vulnerability Description
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.
Source: CVE Program / CVE List V5
CVSS Information
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
Source: CVE Program / CVE List V5
Vulnerability Type
输出中的特殊元素转义处理不恰当(注入)
Source: CVE Program / CVE List V5
Vulnerability Title
René Föhring HtmlSanitizeEx 输入验证错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
WordPress Formidable Forms是WordPress基金会开源的一款表单创建插件。 René Föhring HtmlSanitizeEx 0.3.1版本至1.5.4之前版本存在输入验证错误漏洞，该漏洞源于CSS scrubber对输出中特殊元素的中和不当，未检查不匹配属性值声明模式的输入，允许未经身份验证的远程攻击者将CSS at-rules（包括导入远程样式表）注入到提供给其他用户的页面中。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
rrrene html_sanitize_ex 0.3.1 ~ 1.4.5 cpe:2.3:a:rrrene:html_sanitize_ex:*:*:*:*:*:*:*:*
rrrene html_sanitize_ex 21f90012eb21aa36f4e3701b7547e12faf0f3c8b ~ * cpe:2.3:a:rrrene:html_sanitize_ex:*:*:*:*:*:*:*:*

II. Public POCs for CVE-2026-68747

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-68747

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-68747 (2)

Vendor Advisories for CVE-2026-68747 (2)

Other References for CVE-2026-68747 (1)

Same Patch Batch · rrrene · 2026-08-06 · 6 CVEs total

CVE-2026-68749 8.2 HIGH Quadratic regex backtracking in the html_sanitize_ex CSS scrubber allows CPU-exhaustion de
CVE-2026-68750 8.2 HIGH Quadratic sibling re-flattening in the html_sanitize_ex traversal engine allows CPU-exhaus
CVE-2026-66370 4.8 MEDIUM html_sanitize_ex HTML5 scrubber keeps attacker-supplied form-association attributes, allow
CVE-2026-66829 2.3 LOW html_sanitize_ex HTML5 scrubber keeps attacker-supplied meta refresh, allowing forced cros
CVE-2026-66843 2.3 LOW html_sanitize_ex HTML5 scrubber keeps attacker-supplied `<object>` elements, allowing untr

IV. Related Vulnerabilities

Same product: html_sanitize_ex
Same vendor: rrrene
Same weakness: CWE-74