CVE-2026-70617

Spacebar Server before commit dcfd910 contains a missing authorization vulnerability that allows any authenticated attacker to add themselves to arbitrary group DM channels by sending a PUT request to the channels recipient endpoint without membership verification. Attackers can exploit the unguarded PUT /channels/{channel_id}/recipients/{user_id} handler to join private group DMs, read complete message history, post messages as a participant, and force-add third-party users without their consent.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/spacebarchat/server/commit/dcfd91035e3da42abf5f32d8d86a35219225b3d4
https://github.com/spacebarchat/server/security/advisories/GHSA-g38j-78fh-jm74
https://www.vulncheck.com/advisories/spacebar-server-missing-authorization-via-group-dm-recipient-endpoint
https://github.com/spacebarchat/server/security/advisories/GHSA-g38j-78fh-jm74

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-05 20:17

Updated : 2026-09-16 20:34

NVD link : CVE-2026-70617

Mitre link : CVE-2026-70617

CVE.ORG link : CVE-2026-70617

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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