cve.bz

CVE-2026-77257

8.3 highEPSS 0.4%

High (8.3) in mcp-atlassian mcp atlassian. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in mcp-atlassian 0.22.0.

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, HTTP-exposed Jira and Confluence upload tools pass a caller-provided file_path to local file operations without restricting it to the workspace. A remote MCP caller with tool access can cause the server to read sensitive local files and upload them as Atlassian attachments. The advisory traces the vulnerable input and processing flow through streamable-http, upload_attachment, and file_path, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

Severity

CVSS 4.0

8.3 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

CVSS 3.1

6.5 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
0.4% chance of exploitation in the next 30 days; higher than 32% of CVEs (scores of 2026-10-31)
CWE
CWE-22
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-mrq8-fv7v-hhjgPyPImcp-atlassian<0.22.00.22.0
PYSEC-2026-4098PyPImcp-atlassian<0.22.00.22.0

References

Check your stackJSON