CVE-2026-81527 (GCVE-0-2026-81527)

Vulnerability from cvelistv5 – Published: 2026-08-27 18:32 – Updated: 2026-08-28 15:46
VLAI
Title
NoSQL injection via unquoted constant GroupBy keys in LINQ pipeline translation
Summary
A NoSQL/expression injection weakness exists in the LINQ-to-aggregation query translation layer of the MongoDB C# Driver, in both aggregation expression and query filter translation. When application-supplied values are embedded in certain query constructs, special elements contained within those values are not properly escaped before the resulting query is transmitted to the database, so portions of the value may be interpreted by the database as query logic rather than as data. A user able to supply values that an application incorporates into an affected query may thereby cause unintended data to be returned or query results to be altered.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 15:46 UTC
CWE
  • CWE-943 - Improper Neutralization of Special Elements in Data Query Logic
Assigner
mongodb CNA under the mitre root
CNA scorecard C 70/100 over 204 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MongoDB C# Driver Affected: 2.14.0 , < 3.11.1 (semver)
guessed Create a notification for this product.
Show details on NVD website
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