CVE-2026-58066
SAML signature wrapping allows attacker to impersonate any Rocket.Chat user
Is CVE-2026-58066 being exploited?
Not confirmed. CVE-2026-58066 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.23% probability of exploitation in the next 30 days.
How severe is CVE-2026-58066?
CVE-2026-58066 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-58066?
Yes. A fix has been recorded for CVE-2026-58066. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-58066 affect?
CVE-2026-58066 affects Rocket.Chat server (SAML SSO), Affected versions: before 8.7.0, 8.6.1, 8.5.2, 8.4.5, 8.3.7, 8.2.7, 8.1.7, 8.0.8, 7.10.14. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-58066?
Upgrade to listed fixed versions or disable SAML SSO / restrict IdP until patched
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authentication bypass via SAML signature wrapping; attacker can impersonate arbitrary users and access Rocket.Chat accounts and data.
Immediate action required
- affected< 8.7.0
- affected< 8.6.1
- affected< 8.5.2
- affected< 8.4.5
- affected< 8.3.7
- affected< 8.2.7
- affected< 8.1.7
- affected< 8.0.8
- affected< 7.10.14
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.