Vulnerability · Published Jun 24, 2026 · Assigned by GitHub_M
CVE-2026-45677Rocket.Chat: Lack of SAML Signature Check During Logout Could Lead To DoS
High 8.7
In plain English
A high-severity missing authorization in Rocket.Chat from RocketChat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities).
Official description
Rocket.Chat is an open-source, secure, fully customizable communications platform. Prior to 8.5.0, 8.4.1, 8.3.3, 8.2.3, 8.1.4, 8.0.5, 7.13.7, and 7.10.11, Rocket.Chat's SAML integration does not verify the signature on inbound LogoutRequest messages. An unauthenticated remote attacker who knows a target user's SAML NameID - which major identity providers (Okta, Google Workspace, Microsoft Entra ID, JumpCloud) expose as the user's email address - can craft a valid-looking unsigned LogoutRequest and submit it to the SP logout endpoint. The server processes it as legitimate, immediately destroying the victim's session. Because the attack requires no authentication and no interaction from the victim, it can be repeated in a loop against individual users or scripted across many accounts, effectively rendering the Rocket.Chat instance unusable for SAML-authenticated users. This vulnerability is fixed in 8.5.0, 8.4.1, 8.3.3, 8.2.3, 8.1.4, 8.0.5, 7.13.7, and 7.10.11.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| RocketChat | Rocket.Chat | >= 8.5.0-rc.0, < 8.5.0>= 8.4.0-rc.0, < 8.4.1>= 8.3.0-rc.0, < 8.3.3>= 8.2.0-rc.0, < 8.2.3>= 8.1.0-rc.0, < 8.1.4>= 8.0.0-rc.0, < 8.0.5>= 7.11.0-rc.0, < 7.13.7< 7.10.11 |
Weakness: CWE-862 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N