CVE-2026-106434
Unrecognized payload acceptance in explicit decryption in MongoDB libmongocrypt
MongoDB libmongocryptDatabasesCVSS
5.3MediumExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.11%Chance of exploitation activity in the next 30 days, higher than 1% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
- 1.20.5libmongocryptCVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Description
The explicit decryption component of MongoDB libmongocrypt can return an unrecognized encrypted payload unchanged instead of returning a decryption error. An actor who can modify stored encrypted fields, such as a database writer, server, or network intermediary, can cause an affected application to process the supplied bytes as decrypted plaintext.
Text from CVE List
Affected versions 1
- libmongocryptaffected: 1.5.0 before 1.20.5CVE List