Cyber Resilience

CVE-2026-30917

High

Published: 10 March 2026

Published
10 March 2026
Modified
16 April 2026
KEV Added
Patch
CVSS Score v4 8.8 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:L/SI:L/SA:L/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
EPSS Score 0.0030 21.2th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-30917 is a high-severity Cross-site Scripting (CWE-79) vulnerability. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 21.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability details

Bucket is a MediaWiki extension to store and retrieve structured data on articles. Prior to 2.1.1, a stored XSS can be inserted into any Bucket table field that has a PAGE type, which will execute whenever a user views that…

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table's corresponding Bucket namespace page. This vulnerability is fixed in 2.1.1.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.007 JavaScript Execution
Adversaries may abuse various implementations of JavaScript for execution.
Why these techniques?

Stored XSS in public-facing MediaWiki extension directly enables exploitation of the web app (T1190) and arbitrary JavaScript execution in victim browsers (T1059.007).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References