How severe is CVE-2026-30977?

CVE-2026-30977 has a CVSS 4.0 base score of 2.0, rated low severity.

Is CVE-2026-30977 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-30977?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-30977 have an EU (EUVD) identifier?

Yes. CVE-2026-30977 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10713.

When was CVE-2026-30977 published?

CVE-2026-30977 was published on 2026-03-10 and last updated on 2026-06-17.

CVE-2026-30977

CVE-2026-30977 is a low-severity vulnerability with a CVSS 4.0 base score of 2.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Low (CVSS 4.0 base score 2.0)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-10713
Weakness: CWE-79
Published: 2026-03-10
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-30977?: 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.
How severe is CVE-2026-30977?: CVE-2026-30977 has a CVSS 4.0 base score of 2.0, rated low severity.
Is CVE-2026-30977 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-30977?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-30977 have an EU (EUVD) identifier?: Yes. CVE-2026-30977 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10713.
When was CVE-2026-30977 published?: CVE-2026-30977 was published on 2026-03-10 and last updated on 2026-06-17.

References

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