PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Versions prior to 8.5.10 do not escape `</style>` sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML `<style>` tags, `</style>` in CSS values breaks out of the style context, enabling XSS. Version 8.5.10 fixes the issue.
PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Versions prior to 8.5.10 do not escape </style> sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML <style> tags, </style> in CSS values breaks out of the style context, enabling XSS. Version 8.5.10 fixes the issue.
왜 이 VPI인가 (설명가능 · 실험적)
VPI 산정 기준
| 영향도 | 61.00 |
| 악용 신호(추가 악용신호 없음) | ×1.00 |
| VPI | 61.00 |
VPI 공식 vpi-v1 기준
| 소스 | CVSS 버전 | 기본 점수 | 심각도 | 벡터 문자열 | 평가일 |
|---|---|---|---|---|---|
| NVDNIST | 3.1 | 6.1 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N | 2026. 04. 27. |
| OSV3rd | 3.1 | 6.1 |
| CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| 2026. 04. 26. |