sooperset mcp-atlassian up to 0.21.x Session _make_ssrf_safe_hook server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.5$0-$5k1.85+

Summaryinfo

A vulnerability was found in sooperset mcp-atlassian up to 0.21.x. It has been declared as critical. This issue affects the function _make_ssrf_safe_hook of the component Session Handler. Executing a manipulation can lead to server-side request forgery. This vulnerability is registered as CVE-2026-77261. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in sooperset mcp-atlassian up to 0.21.x. This vulnerability affects the function _make_ssrf_safe_hook of the component Session Handler. The manipulation with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. 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. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-77261 since 08/20/2026. The exploitation appears to be easy. The attack can be initiated remotely. Technical details are known, but there is no available exploit.

Upgrading to version 0.22.0 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.5

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: mcp-atlassian 0.22.0

Timelineinfo

08/20/2026 CVE reserved
09/22/2026 +33 days Advisory disclosed
09/22/2026 +0 days VulDB entry created
09/22/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-77261 (🔒)
GCVE (CVE): GCVE-0-2026-77261
GCVE (VulDB): GCVE-100-408610

Entryinfo

Created: 09/22/2026 20:29
Changes: 09/22/2026 20:29 (66)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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