---
title: "CVE-2026-77260: MCP Atlassian - Information Disclosure"
description: "MCP Atlassian < 0.22.0 contains an information disclosure caused by unconstrained file_path handling in upload_attachment, letting permitted MCP callers upload and retrieve sensitive host files, exploit requires MCP caller permissions."
url: https://panop.io/threat-heartbeat/CVE-2026-77260/
---

# CVE-2026-77260 MCP Atlassian - Information Disclosure

MCP Atlassian < 0.22.0 contains an information disclosure caused by unconstrained file\_path handling in upload\_attachment, letting permitted MCP callers upload and retrieve sensitive host files, exploit requires MCP caller permissions.

CVSS base score 7.5 /10

High

CISA KEV

Not listed

Public exploit

Proof of concept available

Authentication

Not required

EPSS

0.35% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-77260)

## Details

Type

Information Disclosure

Impact

Information Disclosure

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Published

22 September 2026

Updated

15 October 2026

Weakness

[CWE-22](https://cwe.mitre.org/data/definitions/22.html)

## Vendor fix

Upgrade to version 0.22.0 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-77260](https://nvd.nist.gov/vuln/detail/CVE-2026-77260)
- [https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460](https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460)
- [https://github.com/sooperset/mcp-atlassian/pull/1448](https://github.com/sooperset/mcp-atlassian/pull/1448)
- [https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0](https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0)
- [https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-f4p7-qx46-wc5j](https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-f4p7-qx46-wc5j)

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## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

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