CVE-2026-45688

CRITICAL
Published Jun 24, 2026 Modified Jun 26, 2026 CWE-943

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 CAS login handler forwards the client-supplied options.cas.credentialToken value straight into a MongoDB findOne({_id: ...}) query without any runtime type check. TypeScript's string parameter annotation is erased at runtime, so an unauthenticated attacker can substitute a MongoDB query operator ({"$gt": ""}, {"$ne": null}, etc.) for what the server expects to be an opaque ticket string. The injected operator matches the first unexpired document in the credential_tokens collection, bypassing the CAS ticket check entirely. When any legitimate CAS or SAML SSO login is in flight, the attacker's next DDP login call matches the same credential-token row via the NoSQL operator and is issued a full Meteor auth token (userId + token) bound to the victim. The token is immediately usable against the complete REST and DDP surface as that user. If the victim is an administrator, this escalates to full instance compromise via Apps-Engine app install. 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 v3.1 Score

9.1
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS — Exploit Prediction

0.0029
Probability of exploitation
0.21%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-943 CWE-943

References

Frequently Asked Questions

What is CVE-2026-45688? +
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 CAS login handler forwards the client-supplied options.cas.credentialToken value straight into a MongoDB findOne({_id: ...}) query without any runtime type check. TypeScript's string parameter annotation is erased at runtime, so an unauthenticated attacker can substitute a MongoDB query operator ({"$gt": ""}, {"$ne": null}, etc.) for what the server expects to be an opaque ticket string. The injected operator matches the first unexpired document in the credential_tokens collection, bypassing the CAS ticket check entirely. When any legitimate CAS or SAML SSO login is in flight, the attacker's next DDP login call matches the same credential-token row via the NoSQL operator and is issued a full Meteor auth token (userId + token) bound to the victim. The token is immediately usable against the complete REST and DDP surface as that user. If the victim is an administrator, this escalates to full instance compromise via Apps-Engine app install. 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. It has a CVSS v3.1 base score of 9.1 (CRITICAL).
How severe is CVE-2026-45688? +
CVE-2026-45688 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0029, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-45688? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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