CVE-2026-77261: MCP Atlassian — HIGH

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, _make_ssrf_safe_hook is omitted from JiraFetcher and ConfluenceFetcher sessions created through the basic-auth and oauth_pat branches. If an attacker-controlled or compromised...

Full CISO analysis pending enrichment.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
MCP Atlassian	pip	—	No patch
1 dependents 33% patched ~10d to patch Full package profile →

Do you use MCP Atlassian? You're affected.

How severe is it?

CVSS 3.1

7.1 / 10

EPSS

N/A

Exploitation Status

No known exploitation

Sophistication

N/A

What is the attack surface?

AV Network

AC High

PR Low

UI None

S Changed

C High

I Low

A None

What should I do?

No patch available

Monitor for updates. Consider compensating controls or temporary mitigations.

Which compliance frameworks are affected?

Compliance analysis pending. Sign in for full compliance mapping when available.

Frequently Asked Questions

What is CVE-2026-77261?

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, _make_ssrf_safe_hook is omitted from JiraFetcher and ConfluenceFetcher sessions created through the basic-auth and oauth_pat branches. If an attacker-controlled or compromised configured Atlassian instance returns a redirect to an internal address, those sessions can follow the redirect without revalidating its destination. This issue is fixed in version 0.22.0.

Is CVE-2026-77261 actively exploited?

No confirmed active exploitation of CVE-2026-77261 has been reported, but organizations should still patch proactively.

How to fix CVE-2026-77261?

No patch is currently available. Monitor vendor advisories for updates.

What is the CVSS score for CVE-2026-77261?

CVE-2026-77261 has a CVSS v3.1 base score of 7.1 (HIGH).

What are the technical details?

Original Advisory

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, _make_ssrf_safe_hook is omitted from JiraFetcher and ConfluenceFetcher sessions created through the basic-auth and oauth_pat branches. If an attacker-controlled or compromised configured Atlassian instance returns a redirect to an internal address, those sessions can follow the redirect without revalidating its destination. This issue is fixed in version 0.22.0.

Weaknesses (CWE)

CWE-918 Server-Side Request Forgery (SSRF)

CWE-918 — Server-Side Request Forgery (SSRF): The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Source: MITRE CWE corpus.