CVE-2026-106433
Improper state management in MongoDB libmongocrypt can cause provider-specific data to be treated as an incompatible type when cleaning up a key document containing duplicate masterKey fields.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Improper state management in MongoDB libmongocrypt can cause provider-specific data to be treated as an incompatible type when cleaning up a key document containing duplicate masterKey fields. An authenticated actor who can modify key vault documents, or a server that returns such a key document, can cause invalid memory access and invalid frees in the client process. This can terminate the application or corrupt process memory.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.27% probability · 19th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-843
- Affected
- mongodb/libmongocrypt
- Source
- cna@mongodb.com
EPSS moved from 0.3% on 9 October 2026 to 0.3% on 26 October 2026.
References
- https://jira.mongodb.org/browse/MONGOCRYPT-964Vendor Advisory, Issue Tracking
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.