CVE-2026-30977 json
RenderBlocking has Stored XSS in renderblocking-css with Inline Assets mode
published 2026-03-10 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-10713
- cvss
- 2.0
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
RenderBlocking is a MediaWiki extension that allows interface administrators to specify render-blocking CSS and JavaScript. Prior to 0.1.1, there is Stored XSS in renderblocking-css with Inline Assets mode. $wgRenderBlockingInlineAssets = true and editsitecss user rights are required. This vulnerability is fixed in 0.1.1.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 7 mo ago
Exploit prediction
0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 2.0 | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N |
| CNA | 4.0 | 2.0 | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/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 |
Affected products
- lihaohong6 RenderBlocking
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
Sources
- CVE List CVE-2026-30977
- NVD CVE-2026-30977
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.