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Fencer Intel
critical 9.3

CVE-2026-46423 json

Rocket.Chat: SAML signature validation skipped when IdP certificate field is empty

published 4mo ago modified 15d ago also EUVD-2026-39095

cvss
9.3
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 12%
public exploits
0
none known

Summary

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 service provider implementation silently skips both SAML Response and Assertion signature validation when the configured IdP certificate field is empty. The verifySignatures routine performs an early return when serviceProviderOptions.cert is falsy, which is the default state of the setting. Because provider registration only gates on the SAML "enabled" toggle and not on the presence of a certificate, an administrator who enables SAML without pasting an IdP certificate obtains a fully wired, publicly reachable SAML login endpoint that accepts unsigned or attacker-supplied assertions. This is a default-configuration authentication-bypass class: the fail-open branch is reached with no misconfiguration beyond leaving a field at its shipped default. 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.

Patch / fix

  • rocket.chat rocket.chat 7.10.11, 7.13.7, 8.0.5, 8.1.4, 8.2.3, 8.3.3, 8.4.1, 8.5.0

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
total
Assessed
4mo ago

Exploit prediction

0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 4.0 9.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N
CNA 4.0 9.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/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

Affected products

  • RocketChat Rocket.Chat

Classification

Weakness
  • CWE-347 Improper Verification of Cryptographic Signature

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.