CVE-2026-88026 Regular expression injection via unescaped characters in LINQ query translation in MongoDB C# Driver
An authenticated user can manipulate LINQ queries to bypass filters and read unintended database records via regex injection.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-88026?
CVE-2026-88026 is a high-severity vulnerability in MongoDB C# Driver, published on 10 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Improper neutralization of regular-expression metacharacters in the LINQ query translation component of the MongoDB C# Driver can cause a caller-supplied character sequence to alter a regular-expression predicate generated by an affected application. An authenticated user who can influence such a value may cause the application to return records beyond those intended by the original filter.
Weakness: CWE-943
Which versions are affected by CVE-2026-88026?
It affects 1 product.
Products include Mongodb C\# Driver.
How do I fix CVE-2026-88026?
No fix has been published for CVE-2026-88026 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-88026 being exploited?
There is no known exploitation of CVE-2026-88026 in the wild and no public exploit code.
Other vulnerabilities in MongoDB C# Driver
- CVE-2026-81529 Connection-option injection via unescaped settings in the canonical MongoDB URL builder
- CVE-2026-81527 NoSQL injection via unquoted constant GroupBy keys in LINQ pipeline translation
- CVE-2026-81530 KMS master key exposure via unredacted credential serialization in driver settings string
- CVE-2022-48282 Deserializing compromised object with MongoDB .NET/C# Driver may cause remote code execution
- CVE-2026-88025 GridFS data disclosure and deletion via query-operator injection in file IDs in the MongoDB C# Driver
Sources
Also known as GHSA-j7j2-rrxf-5xvf.