CVE-2026-77248Public exploitNetwork attack vectorHinoki check available

Unauthenticated local file disclosure via unrestricted upload paths

Published Sep 22, 2026 · Updated Sep 22, 2026

Path traversal in sooperset MCP Atlassian before 0.22.0 allows remote attackers to read files available to the server process. The streamable HTTP transport accepts requests without a user identity, falls back to operator credentials, and passes upload_attachment's caller-controlled file_path to open() without validation. Reachability requires the HTTP transport and an attachment destination the operator account can write; exposed data is limited to files readable by the MCP process.

CVSS severity8.6
High
EPSS probability0.41%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Get started

Summary

What happened

Path traversal in sooperset MCP Atlassian before 0.22.0 allows remote attackers to read files available to the server process. The streamable HTTP transport accepts requests without a user identity, falls back to operator credentials, and passes upload_attachment's caller-controlled file_path to open() without validation. Reachability requires the HTTP transport and an attachment destination the operator account can write; exposed data is limited to files readable by the MCP process.

The record

CVE
CVE-2026-77248
Published
Sep 22, 2026
Updated
Sep 22, 2026
Vendor
sooperset
Product
MCP Atlassian
Classifications
T1567
Attack vector
network
Privileges
unauthenticated

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

Compare your product and version with the public record. A matching version still requires validation against your environment.

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 privilegesunauthenticated

What is affected?

sooperset · MCP Atlassianversion=< 0.22.0

Published CVSS scores

8.6GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1567Exfiltration Over Web Service

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Get started to see how Hinoki identifies affected software and validates exploitability in your environment.

Get started