CVE-2026-45677

HIGHPre-NVD 8.78.7—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 63% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
8.7EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.7Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
8.7
EG Score
8.7(medium)
EG Risk
44(Track)
EG Risk 44/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity87% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
37%
KEV
Not listed

Published

June 24, 2026

Last Modified

June 25, 2026

Advisory Details (1)

Auto-updated Jun 24, 2026
Patch available. Sources: github.
github Patch Available

Lack of SAML Signature Check During Logout Could Lead To DoS · Advisory · RocketChat/Rocket.Chat · GitHub

https://github.com/RocketChat/Rocket.Chat/security/advisories/GHSA-pw6f-q8ww-vqfq

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 12× in last 7d / 38× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-03 10:36 UTCEPSS rescore
  2. 2026-08-01 15:03 UTCEG score recompute
  3. 2026-08-01 04:16 UTCEPSS rescore
  4. 2026-07-31 03:24 UTCEG score recompute
  5. 2026-07-30 16:28 UTCEPSS rescore
  6. 2026-07-30 14:51 UTCEG score recompute
  7. 2026-07-30 02:09 UTCEG score recompute
  8. 2026-07-30 01:30 UTCEPSS rescore
  9. 2026-07-29 00:39 UTCEG score recompute
  10. 2026-07-28 15:36 UTCEPSS rescore
  11. 2026-07-27 17:32 UTCEG score recompute
  12. 2026-07-27 14:13 UTCEPSS rescore
  13. 2026-07-26 15:23 UTCEG score recompute
  14. 2026-07-26 14:54 UTCEPSS rescore
  15. 2026-07-26 14:54 UTCEPSS rescore
  16. 2026-07-25 14:18 UTCEPSS rescore
  17. 2026-07-24 14:17 UTCEPSS rescore
  18. 2026-07-23 14:18 UTCEPSS rescore
  19. 2026-07-23 03:16 UTCEG score recompute
  20. 2026-07-22 14:08 UTCEPSS rescore
  21. 2026-07-21 15:24 UTCEPSS rescore
  22. 2026-07-20 17:08 UTCEPSS rescore
  23. 2026-07-19 14:31 UTCEPSS rescore
  24. 2026-07-19 02:29 UTCEPSS rescore
  25. 2026-07-18 10:04 UTCEPSS rescore
Show 25 more
  1. 2026-07-16 17:03 UTCEPSS rescore
  2. 2026-07-15 16:57 UTCEPSS rescore
  3. 2026-07-15 02:00 UTCEPSS rescore
  4. 2026-07-13 22:30 UTCEPSS rescore
  5. 2026-07-13 06:13 UTCEPSS rescore
  6. 2026-07-12 05:46 UTCEPSS rescore
  7. 2026-07-11 08:27 UTCEPSS rescore
  8. 2026-07-09 19:10 UTCEPSS rescore
  9. 2026-07-08 15:16 UTCEPSS rescore
  10. 2026-07-07 13:46 UTCEPSS rescore
  11. 2026-07-06 16:27 UTCEPSS rescore
  12. 2026-07-06 02:23 UTCEPSS rescore
  13. 2026-07-05 02:30 UTCEPSS rescore
  14. 2026-07-04 06:31 UTCEPSS rescore
  15. 2026-07-01 15:07 UTCEPSS rescore
  16. 2026-06-30 23:22 UTCEPSS rescore
  17. 2026-06-29 14:06 UTCEPSS rescore
  18. 2026-06-29 14:06 UTCEPSS rescore
  19. 2026-06-28 14:07 UTCEPSS rescore
  20. 2026-06-28 04:56 UTCEPSS rescore
  21. 2026-06-28 04:56 UTCEPSS rescore
  22. 2026-06-27 03:08 UTCEPSS rescore
  23. 2026-06-25 13:49 UTCEPSS rescore
  24. 2026-06-24 22:03 UTCEG score recompute
  25. 2026-06-24 22:03 UTCNVD updatefirst tracked

Frequently asked(5)

What is CVE-2026-45677?
CVE-2026-45677 is a high vulnerability published on June 24, 2026. 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…
When was CVE-2026-45677 disclosed?
CVE-2026-45677 was first published in the National Vulnerability Database on June 24, 2026, with the most recent update on June 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-45677 actively exploited?
CVE-2026-45677 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 63.0% of all scored CVEs.
What is the CVSS score of CVE-2026-45677?
CVE-2026-45677 has a CVSS v3 base score of 8.7 (NVD).
How do I remediate CVE-2026-45677?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45677, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-45677

Explore →

Is Your Infrastructure Affected by CVE-2026-45677?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs