CVE-2026-84971
Persistent client crash loop via undersized FLE2 insert-update ciphertext in decryption path
- State
- Published
- Severity
- 7.1 High
- Published
- Sep 3, 2026
- Updated
- Sep 3, 2026
- Reserved
- Sep 2, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 7.1 High | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | mongodb |
| 3.1 | 6.5 Medium | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | mongodb |
Weaknesses
- CWE-617 Reachable Assertion
Affected Products
| Product | Versions |
|---|---|
libmongocryptMongoDB |
|
References
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