Intel

CVE-2026-77258

mcp-atlassian: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (CVE-2026-77258)

highEPSS 0.3%

Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, upload_attachment in src/mcp_atlassian/confluence/attachments.py accepts a caller-controlled file_path and opens the selected server-local file without restricting it to the workspace. A permitted Confluence MCP caller can upload the file as an attachment and disclose data readable by the server process. This issue is fixed in version 0.22.0.

Source: OSV (Open Source Vulnerabilities)NVD (NIST)GitHub Security Advisoriescvelistv5

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

pypimcp-atlassian
0.10.00.10.10.10.20.10.30.10.40.10.50.10.60.1.10.1.100.11.00.1.110.11.10.11.100.11.110.11.120.1.120.11.20.11.2a20.1.130.11.30.1.140.11.40.1.150.11.50.1.160.11.60.11.70.11.80.11.90.1.20.12.00.1.30.13.00.13.10.1.40.14.00.14.10.14.20.14.30.15.00.1.60.16.00.16.10.1.70.17.00.1.80.18.00.18.1

Metrics

XIEM Effective CVSS
7.7
Source: cna-v3
EPSS percentile
25.4 %
Elevated — this CVE ranks above at least 10% of all CVEs scored today.
KEV status
—
Show all metrics
Severity
high
Priority score
73.68
Exploit maturity
no public PoC known
CVSS v3
7.7
EPSS score
0.3 %
Low — model estimates < 1% exploitation likelihood.
Published
2026-10-01 16:38 UTC
CWE
CWE-22

Weakness classes (CWE)

  • CWE-22Base

    Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

    The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

    cwe.mitre.org →

References & sources

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. Initial Analysis2026-09-29 14:01 UTC· nvd@nist.gov
    • CPE Configuration: OR *cpe:2.3:a:mcp-atlassian:mcp_atlassian:*:*:*:*:*:*:*:* versions up to (excluding) 0.22.0
    • Reference Type: GitHub, Inc.: https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460 Types: Patch
    • Reference Type: GitHub, Inc.: https://github.com/sooperset/mcp-atlassian/pull/1448 Types: Issue Tracking, Patch
    • Reference Type: GitHub, Inc.: https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0 Types: Release Notes
  2. CVE Modified2026-09-26 00:16 UTC· 134c704f-9b21-4f2e-91b3-4a467353bcc0
    • Reference: https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-93xw-j965-9mx3
    • SSVC: {"id":"CVE-2026-77258","role":"CISA Coordinator","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalIm…
  3. New CVE Received2026-09-22 18:17 UTC· security-advisories@github.com
    • Description: MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, upload_attachment in src/mcp_atlassian/confluence/attachments.py accepts a caller-controlled file_path and opens the selected server-local file without restricting it to the workspace. A permitted Confluence MCP caller can upload the file as an attachment and disclose data readable by the server process. This issue is fixed in version 0.22.0.
    • CVSS V3.1: AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
    • CWE: CWE-22
    • Affected: New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/77xxx/CVE-2026-77258.json">CVE-2026-77258</a>