CVE-2026-77244Public exploitNetwork attack vectorHinoki check available

Unauthenticated operator access via credential fallback

Published Sep 22, 2026 · Updated Sep 22, 2026

Authentication bypass in MCP Atlassian before 0.22.0 allows remote attackers to use the operator's Jira or Confluence access. The HTTP transport accepts requests without verified identity, while its fetchers fall back to globally configured operator credentials. Network reachability to an HTTP deployment is sufficient to read or write data within that operator account's permissions.

CVSS severity10.0
Critical
EPSS probability0.29%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authentication bypass in MCP Atlassian before 0.22.0 allows remote attackers to use the operator's Jira or Confluence access. The HTTP transport accepts requests without verified identity, while its fetchers fall back to globally configured operator credentials. Network reachability to an HTTP deployment is sufficient to read or write data within that operator account's permissions.

The record

CVE
CVE-2026-77244
Published
Sep 22, 2026
Updated
Sep 22, 2026
Vendor
sooperset
Product
MCP Atlassian
Classifications
CWE-303, CWE-862, CWE-287, T1078
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

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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 privilegesunauthenticated

What is affected?

sooperset · MCP Atlassianversion=< 0.22.0

Published CVSS scores

10.0soopersetCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/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

CWE-303Incorrect Implementation of Authentication Algorithm
CWE-862Missing Authorization
CWE-287Improper Authentication
T1078Valid Accounts

Public exploit references

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

Technologies

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