CVE-2026-106437: medium-severity vulnerability in MongoDB C Driver
Out-of-bounds read and write via undersized BSON buffer reservation in MongoDB C Driver
Published
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.9epss 0.1%
The BSON buffer-reservation API in the MongoDB C Driver can record a length smaller than the five-byte BSON minimum. Later append or comparison operations can underflow unsigned length calculations and read or write outside the document buffer. An actor who can influence the length supplied by an embedding application can cause the application to terminate or read or corrupt adjacent process memory. Reaching this issue requires the application to pass an undersized value to bson_reserve_buffer and then perform an affected operation.
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
Affected products
MongoDB · C DriverRelated CVEs — MongoDB C Driver
In the same product, most dangerous first.
CVE-2026-96746HIGHHeap buffer overflow via mid-scan command list growth in client topology monitoringEPSS 0.4%CVE-2026-84963MEDIUMSilent field truncation via unchecked int cast of huge JSON string values in JSON-to-BSON parserEPSS 0.3%CVE-2026-84969MEDIUMHeap overflow via truncated base64 encoding of binary fields in length-limited JSON outputEPSS 0.3%CVE-2026-81524MEDIUMCross-tenant database retargeting via dot/NUL injection in namespace strings in the C DriverEPSS 0.3%CVE-2026-88036MEDIUMGridFS data disclosure and deletion via query-operator injection in file IDs in the MongoDB C DriverEPSS 0.3%CVE-2026-84964HIGHHeap corruption via OCSP request double free from crafted multi-URL certificate in TLS clientEPSS 0.3%