Medium severity · published Sep 10, 2026
CVE-2026-88026
Regular expression injection via unescaped characters in LINQ query translation in MongoDB C# Driver
6.5
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
2.14.0 through 3.11.1 · source: vendor
CD
C# Driver · Mongodb
2.14.0 before 3.11.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-88026
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-88026
Vendor Advisory
https://jira.mongodb.org/browse/CSHARP-6177
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