GHSA-h7wj-5v37-59r2: mcp-atlassian (CVE-2026-77269)

Package	Ecosystem	Affected	Fixed in
mcp-atlassian	PyPI	<0.22.0	0.22.0

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Affected versions of mcp-atlassian before 0.22.0 do not check that the file_path parameter of the Confluence attachment upload tools stays inside an allowed directory before opening the file. An attacker who can call these tools can read files the MCP server process can access, such as SSH keys or .env files, and upload them to Confluence. Upgrade to mcp-atlassian 0.22.0 or later. The source notes this is an incomplete fix for CVE-2026-27825, which covered downloads but not uploads.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.5	Medium	3.1	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0043, the 37th percentile, on 10 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:09 UTC First seen by agentprime
31 Oct 2026, 14:09 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.