EUVD-2026-54084
GHSA-8rjf-8hw9-j63g
Severity by source
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Primary rating from Vendor (EEF) · only source for this CVE.
CVSS VectorVendor: EEF
Lifecycle Timeline
3DescriptionCVE.org
Inefficient Regular Expression Complexity vulnerability in the CSS scrubber in rrrene html_sanitize_ex allows an unauthenticated remote attacker to exhaust server CPU via a long CSS declaration in sanitized HTML. The declaration regex in HtmlSanitizeEx.Scrubber.CSS.scrub/1 matches the property name with an unbounded greedy [-\w]+ followed by a mandatory :, so a long run of word characters not followed by a colon makes the engine give back one character at a time and retry the colon at every start offset. The work is quadratic in the length of the run, and no length cap is applied to the CSS handed to the scrubber. An 80 KB <style> body costs roughly 2.4 seconds of scheduler time, so a few concurrent requests saturate the BEAM scheduler pool and make the application unresponsive.
The impact is CPU exhaustion only. Nothing is read, modified or disclosed.
This issue affects html_sanitize_ex: from 0.3.1 before 1.5.3.
AnalysisAI
CPU exhaustion via quadratic regex backtracking in rrrene/html_sanitize_ex, an Elixir HTML sanitization library, allows unauthenticated remote attackers to saturate the BEAM scheduler pool and render applications unresponsive. The CSS scrubber's declaration regex applies an unbounded greedy quantifier on the property-name token; a crafted 80 KB style body containing no valid CSS colon costs approximately 2.4 seconds of scheduler time per request, meaning a handful of concurrent requests fully deny service. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Recommended ActionAI
Within 24 hours, inventory all applications and services running vulnerable versions of html_sanitize_ex (0.3.1 through 1.5.2 inclusive) to identify scope of exposure. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
More in Html Sanitize Ex
View allQuadratic CPU and memory exhaustion in html_sanitize_ex affects all applications that accept user-supplied HTML for sani
html_sanitize_ex's HTML5 scrubber (versions 0.3.1 through 1.5.2) permits the `form` and `formaction` attributes to survi
Open redirect in html_sanitize_ex (Elixir, versions 0.3.1 through 1.5.2) allows remote attackers to force page visitors
html_sanitize_ex's HTML5 scrubber (versions 0.3.1 through before 1.5.3) passes attacker-controlled URIs through the `dat
CSS at-rule injection in html_sanitize_ex (Elixir, versions 0.3.1-1.5.3) allows unauthenticated remote users to embed `@
Same technique Denial Of Service
View allShare
External POC / Exploit Code
Leaving vuln.today