CVE-2026-77259Public exploitNetwork attack vectorHinoki check available

Server file disclosure via unchecked attachment path

Published Sep 22, 2026 · Updated Sep 22, 2026

Path traversal in sooperset MCP Atlassian before 0.22.0 allows remote authenticated users to read server-local files through Confluence. The _upload_attachment_direct function passes caller-controlled file_path data to open in binary-read mode without applying validate_safe_path. An MCP client with tool access can expose any file readable by the server process, while prompt injection can supply the malicious path indirectly.

CVSS severity7.7
High
EPSS probability0.41%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Path traversal in sooperset MCP Atlassian before 0.22.0 allows remote authenticated users to read server-local files through Confluence. The _upload_attachment_direct function passes caller-controlled file_path data to open in binary-read mode without applying validate_safe_path. An MCP client with tool access can expose any file readable by the server process, while prompt injection can supply the malicious path indirectly.

The record

CVE
CVE-2026-77259
Published
Sep 22, 2026
Updated
Sep 22, 2026
Vendor
sooperset
Product
MCP Atlassian
Classifications
CWE-22, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 22, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.22.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

sooperset · MCP Atlassianversion=< 0.22.0

Published CVSS scores

7.7soopersetCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

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