Medium severity · published Aug 27, 2026
CVE-2026-81524
Cross-tenant database retargeting via dot/NUL injection in namespace strings in the C Driver
5.4
CVSS
0.3%
EPSS
No
On KEV
Description
A weakness in the MongoDB C Driver allows special elements in caller-supplied database and collection name components to pass without sanitization when the driver composes the target namespace for an operation. An application that incorporates untrusted input into these name components can have operations directed at a resource other than the one intended.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 19% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
1.0.0 before 2.5.1 · source: vendor
CD
C Driver · Mongodb
1.0.0 before 2.5.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-81524
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-81524
Product
https://github.com/mongodb/mongo-c-driver/releases/tag/2.5.1
Vendor Advisory
https://jira.mongodb.org/browse/CDRIVER-6424
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