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archive/Patch now/AIR-2026-0174
closedclosed 22 Sep 2026Patch now2 Disclosed vulnerabilityAI

CVE-2026-77251: MCP Atlassian access control bypass in search and board APIs

mcp-atlassian

An access control flaw in MCP Atlassian before 0.22.0 permits callers to query restricted Jira projects, Confluence spaces, or boards. Incomplete validation of syntax and filters allows unauthorized data access when broader credentials are used.

disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why

CVSS
8.3
EPSS
<0.01 · top 82% · 2026-11-13
EPSS scores by FIRST
fix status
Fix status unknown
first report
22 Sep 2026
last update
22 Sep 2026
CVE ids
CVE-2026-77251other records

Timeline · 1

  1. 22 Sep 2026CVE-2026-77251: MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira).

Sources · 1

Advisories and databases

  1. 2026-09-22
    CVE-2026-77251: MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira).
    NVD · nvd.nist.gov/vuln/detail/CVE-2026-77251

Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.

Classification

lane
Patch now
AI role
Attack on AI
categories
Infrastructure vulnerability
severity
2 · Disclosed vulnerability
fix status
Fix status unknown
targets
Framework / tooling
owasp llm top 10
LLM03:2025 Supply Chain
mitre atlas
no technique for these categories
tags
mcpatlassian
dates
happened 22 Sep 2026 · first reported 22 Sep 2026
origin
NVD
Vulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
record
confidence 0.95 · created 2026-10-18 06:33Z · updated 2026-10-18 06:33Z

Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned

Copy a brief

This record as a short Markdown brief, for a ticket, a chat or a coding agent.

the brief as text
# CVE-2026-77251: MCP Atlassian access control bypass in search and board APIs

https://gcdradar.vercel.app/incidents/cve-2026-77251-mcp-atlassian-access-control-bypass-in-search · AIR-2026-0174 · closed 2026-09-22

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-09-22
- AI role: Attack on AI
- Products: mcp-atlassian
- CVE ids: CVE-2026-77251
- CVSS: 8.3

## Summary

An access control flaw in MCP Atlassian before 0.22.0 permits callers to query restricted Jira projects, Confluence spaces, or boards. Incomplete validation of syntax and filters allows unauthorized data access when broader credentials are used.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-09-22: CVE-2026-77251: MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). (https://nvd.nist.gov/vuln/detail/CVE-2026-77251)

## Sources

- 2026-09-22 NVD: CVE-2026-77251: MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). https://nvd.nist.gov/vuln/detail/CVE-2026-77251

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.

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