CVE-2026-93761 Denial of service via unbounded regex matching in Mongoid's in-memory query matcher
An attacker can cause denial of service in applications using Mongoid by supplying input that triggers excessive regex processing.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-93761?
CVE-2026-93761 is a high-severity denial of service vulnerability in MongoDB Inc. Mongoid, published on 18 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.
Weakness: CWE-1333
Which versions are affected by CVE-2026-93761?
It affects 1 product.
Products include Mongodb Mongoid.
How do I fix CVE-2026-93761?
No fix has been published for CVE-2026-93761 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-93761 being exploited?
There is no known exploitation of CVE-2026-93761 in the wild and no public exploit code.
Other vulnerabilities in MongoDB Inc. Mongoid
- CVE-2026-93762 Data deletion and attribute disclosure via field-name method injection in in-memory queries
- CVE-2026-93759 Server-side JavaScript injection via string query criteria bypassing the strict operator allowlist
- CVE-2026-93758 Cross-principal document update, theft, and deletion via unvalidated id in nested attributes
- CVE-2026-93760 NoSQL injection of JavaScript-executing query operators via unsafe-by-default operator guard
- CVE-2026-93765 Document deletion and process crash via unvalidated method-name dispatch in atomic pop operation
Sources
Also known as GHSA-6c34-f5wx-m58m.