CVE-2026-77256

Published: Set 22, 2026 Last Modified: Set 23, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,3
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the plaintext OAuth fallback file containing refresh and access tokens is written with permissions inherited from the process umask. Under common or permissive configurations, other local users can read the backup and retain Atlassian access through the refresh token. The advisory traces the vulnerable input and processing flow through OAuthConfig._save_tokens_to_file, refresh_token, access_token, and umask, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0041
Percentile
0,3th
Updated

Single Data Point

Only one EPSS measurement is available for this CVE. Trend analysis requires multiple data points over time.

732

Incorrect Permission Assignment for Critical Resource

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Access Control Integrity Other
Potential Impacts:
Read Application Data Read Files Or Directories Gain Privileges Or Assume Identity Modify Application Data Other
Applicable Platforms
Technologies: Not Technology-Specific, Cloud Computing
Likelihood of Exploit: High
View CWE Details
https://github.com/sooperset/mcp-atlassian/security/advisor…
https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-76pr-5669-3…
https://github.com/sooperset/mcp-atlassian/commit/b04173347…
https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c2…
https://github.com/sooperset/mcp-atlassian/pull/1448
https://github.com/sooperset/mcp-atlassian/pull/1448
https://github.com/sooperset/mcp-atlassian/releases/tag/v0.…
https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0
https://github.com/sooperset/mcp-atlassian/security/advisor…
https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-76pr-5669-3…