CVE-2026-84971: CWE-617: Reachable Assertion in MongoDB libmongocrypt
Improper handling of an unexpected value size in the decryption path of a client-side encryption library can cause a failed internal check that terminates the process using the library. A party able to place a suitably formed encrypted value where an application will decrypt it, or able to control the responses the application receives, may cause that application to stop running.
CVE-2026-84971: CWE-617: Reachable Assertion in MongoDB libmongocrypt
Description
Improper handling of an unexpected value size in the decryption path of a client-side encryption library can cause a failed internal check that terminates the process using the library. A party able to place a suitably formed encrypted value where an application will decrypt it, or able to control the responses the application receives, may cause that application to stop running.
CVSS v4.0
Score 7.1high
Affected software
Weaknesses
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mongodb
- Date Reserved
- 2026-09-02T17:58:52.743Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a998d5bacd9273b4916fcae
Added to database: 09/03/2026, 15:08:11 UTC
Last updated: 09/03/2026, 20:22:50 UTC
Views: 9
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