CVE-2026-120955: high-severity vulnerability in MongoDB C Driver
MongoDB C Driver Modern GridFS mongoc_gridfs_bucket_download_to_stream() Aborts Application on Malformed GridFS Metadata
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.4%
The GridFS file download API in the MongoDB C Driver does not check the result of an internal operation under certain error conditions during file retrieval. This can cause the process to terminate when stream operations continue. A user who can influence file download parameters can trigger this condition, which may result in service unavailability for applications using the affected API.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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-2026-120678HIGHMongoDB C Driver leaks the decompressed reply buffer when an OP_COMPRESSED reply fails to parse (denial of service)EPSS 0.4%CVE-2026-120684MEDIUMMongoDB C Driver GridFS gap lets a shared writer recover a protected client's passwordEPSS 0.3%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%