# CVE-2026-73496: MCP Atlassian: Arbitrary server-side file read via attachment upload

> Attackers can read arbitrary server files and credentials via path traversal in attachment upload tools in remote deployments.

- **Severity:** High 7.7 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Sep 2026
- **Updated:** 16 Sep 2026
- **Also known as:** GHSA-wm45-qh3g-v83f

## What is CVE-2026-73496?

CVE-2026-73496 is a high-severity path traversal vulnerability in sooperset mcp-atlassian, published on 14 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the confluence_upload_attachment and confluence_upload_attachments tools pass a client-controlled file_path through src/mcp_atlassian/confluence/attachments.py upload_attachment, and the jira_update_issue attachments parameter reaches src/mcp_atlassian/jira/attachments.py upload_attachment, without confining either path to an approved server workspace. In a remote HTTP, SSE, or multi-user deployment, absolute or traversing paths are resolved on the MCP server and uploaded to Atlassian, allowing a client with write-tool access to disclose server files, environment-held Atlassian credentials, or another tenant's data. A local single-user stdio deployment does not cross this trust boundary because the server runs in the caller's environment. This issue is fixed in version 0.22.0.

Weakness: CWE-73 (External Control of File Name or Path), CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-73496?

2 open source packages ship an affected version, including mcp-atlassian.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mcp-atlassian` | PyPI | All versions | 0.22.0 |
| `mcp-atlassian` | PyPI | All versions | 0.22.0 |

## How do I fix CVE-2026-73496?

Upgrade mcp-atlassian to 0.22.0 or later.

## Is CVE-2026-73496 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73496 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73496 and fix it if it is affected.

What it is: CVE-2026-73496 is a high-severity path traversal vulnerability in sooperset mcp-atlassian, published on 14 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73496 exists.

Affected packages and fixed versions:
- mcp-atlassian (PyPI): affected all versions; fixed in 0.22.0
- mcp-atlassian (PyPI): affected all versions; fixed in 0.22.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-73496/ (Markdown: https://insights.sbomify.com/CVE-2026-73496/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73496
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73496
- OSV: https://osv.dev/vulnerability/CVE-2026-73496

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73496/
Summaries are generated and may contain mistakes; the official description above is the record.