CVE-2025-14847: MongoDB and MongoDB Server Improper Handling of Length Parameter Inconsistency Vulnerability

High severity, CVSS 7.5. Actively exploited: in CISA KEV since 2025-12-29. EPSS: 83.2% chance of exploitation in the next 30 days.

Mismatched length fields in Zlib compressed protocol headers may allow a read of uninitialized heap memory by an unauthenticated client. This issue affects all MongoDB Server v7.0 prior to 7.0.28 versions, MongoDB Server v8.0 versions prior to 8.0.17, MongoDB Server v8.2 versions prior to 8.2.3, MongoDB Server v6.0 versions prior to 6.0.27, MongoDB Server v5.0 versions prior to 5.0.32, MongoDB Server v4.4 versions prior to 4.4.30, MongoDB Server v4.2 versions greater than or equal to 4.2.0, MongoDB Server v4.0 versions greater than or equal to 4.0.0, and MongoDB Server v3.6 versions greater than or equal to 3.6.0.

Affected products

• MongoDB MongoDB: from 3.6.0, before 4.4.30 (fixed in 4.4.30); from 5.0.0, before 5.0.32 (fixed in 5.0.32); from 6.0.0, before 6.0.27 (fixed in 6.0.27); from 7.0.0, before 7.0.28 (fixed in 7.0.28); from 8.0.0, before 8.0.17 (fixed in 8.0.17); from 8.2.0, before 8.2.3 (fixed in 8.2.3)

Published 2025-12-19. Last modified 2026-06-17.