CVE-2026-81528 (GCVE-0-2026-81528)

Vulnerability from cvelistv5 – Published: 2026-08-27 18:32 – Updated: 2026-08-28 15:45
VLAI
Title
NoSQL injection via array replacement bypassing update shape validation in driver write path
Summary
A MongoDB C# driver document-replacement code path omits the element-name/shape validation that the equivalent write paths apply, so a value supplied as a replacement is forwarded to the server without neutralization of query-language special elements. An application that passes untrusted, loosely-typed input as a replacement value therefore allows that input to be interpreted by the database as update logic rather than as data, executing under the application's own database credentials. Applications using strongly-typed document mappings are not affected.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 15:45 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: 2.9.0 , < 3.11.1 (semver)
guessed Create a notification for this product.
Show details on NVD website
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