CVE-2026-81522: high-severity vulnerability in MongoDB C++ Driver
Cross-tenant database retargeting via dot/NUL injection in namespace strings in the C++ Driver
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.6epss 0.5%
A weakness in the MongoDB C++ Driver's handling of caller-supplied namespace identifiers allows special characters embedded in those identifiers. An application that builds a namespace identifier from untrusted input without validating it may therefore have its operation directed at a different target than intended. This can result in limited unauthorized read and write access to data belonging to another logical tenant of the affected application.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Affected products
MongoDB · C++ DriverRelated CVEs — MongoDB C++ Driver
In the same product, most dangerous first.
CVE-2026-88034MEDIUMGridFS data disclosure and deletion via query-operator injection in file IDs in the MongoDB C++ DriverEPSS 0.5%CVE-2026-106430MEDIUMQuery and rename target confusion via embedded NUL truncation in MongoDB C++ DriverEPSS 0.2%CVE-2026-84966MEDIUMBSON element injection via NUL-embedded document keys in builder appendEPSS 0.1%CVE-2026-84970MEDIUMHeap over-read or silent misparse via 32-bit truncation of JSON length in BSON JSON parserEPSS 0.1%