CVE-2026-45677

HIGH

CVSS v4.0: 8.7 · EPSS: 0.0045 (35.9 percentile)

NetworkNo privilegesNo user interactionMissing AuthorizationVendor advisory ref

Source data as of:

At a glance

Severity
HIGH
CVSS
8.7 v4.0 · NVD
EPSS
0.0045 (35.9 percentile) · FIRST.org
CISA KEV
No
Type
Missing Authorization · NVD CWE
Attack conditions (CVSS vector)
NetworkNo privilegesNo user interaction · Source: NVD Vector
Published
2026-06-24 · Modified: 2026-06-25

CVSS / EPSS / KEV

CVSS v4.0 8.7 / 10 HIGH Source: NVD
EPSS 0.0045 35.9 percentile Source: FIRST.org
CISA KEV No Source: CISA

Source — CVSS: NVD · EPSS: FIRST.org · KEV: CISA. Data & Sources

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.

Record details

CVE ID
CVE-2026-45677
CVSS (v4.0)
8.7 (HIGH)
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS
0.0045 (35.9 percentile) — 2026-06-26
CISA KEV
No
Weakness (CWE)
CWE-862
Affected configurations (CPE)
0
Published
2026-06-24
Modified
2026-06-25
Status
Deferred

References

Reference URLs as listed by NVD, grouped by a mechanical match on the link's host/pattern. Labels describe the link type only.