CVE-2026-45677Rocket.Chat: Lack of SAML Signature Check During Logout Could Lead To DoS
- 8.7HighCVSS base score
- 0.68%Exploitation in 30 daysEPSS · top 47% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By GitHub_M
- 43 days later
· 43 days later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High8.7 | 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 |
| NVDNVD · Deferred | 4.0 | High8.7 | 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 (exploitation in 30 days)
- 0.68% · top 47% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.
Affected products
- affected >= 8.5.0-rc.0, < 8.5.0
- affected >= 8.4.0-rc.0, < 8.4.1
- affected >= 8.3.0-rc.0, < 8.3.3
- affected >= 8.2.0-rc.0, < 8.2.3
- affected >= 8.1.0-rc.0, < 8.1.4
- affected >= 8.0.0-rc.0, < 8.0.5
- affected >= 7.11.0-rc.0, < 7.13.7
- affected < 7.10.11
References
References1
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-39091 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-45677)Record last updated .