CVE-2026-53711: ibm mcp-context-forge Cross-site Scripting
Vulnerability summary
CVE-2026-53711 is a medium (CVSS 5.1) Cross-site Scripting vulnerability in ibm mcp-context-forge. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 28.8% of scored vulnerabilities.
Timeline
- 13-10-2026PublishedVulnerability first disclosed.
- 13-10-2026Last modifiedVulnerability information updated.
Description
MCP Context Forge provides an MCP Admin UI for managing gateway resources. From 0.2.0 until 0.3.1, the Global Prompts feature stores a prompt template without sufficient output encoding before the MCP Admin UI renders it. An authenticated attacker can save markup containing script-capable event handlers, and the code executes when another user views the saved prompt. The stored cross-site scripting can alter the interface, present phishing content, observe keystrokes available to the page, and act with the viewer's browser session. This issue is fixed in version 0.3.1.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST5.1MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/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
EPSS trend
Probability
0.36%
Chance of exploitation in the next 30 days
Percentile
29%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ibm1 product
- mcp-context-forge≥ 0.2.0, < 0.3.1
1 vendor · 1 product
References
4 links- github.com/IBM/mcp-context-forge/security/advisories/GHSA-x6gc-rm5j-55mwX Refsource CONFIRM
- github.com/IBM/mcp-context-forge/pull/337X Refsource MISC
- github.com/IBM/mcp-context-forge/releases/tag/v0.3.1X Refsource MISC