High severity · published May 20, 2026
CVE-2026-9100
Heap memory out of bounds read and crash in C Driver legacy GridFS file reader
7.1
CVSS
0.3%
EPSS
No
On KEV
Description
The MongoDB C Driver's legacy GridFS API accepts malformed file metadata from the database without adequate validation. Crafted documents in a GridFS collection may cause any application that reads those files via the legacy API to either crash (via a division-by-zero) or silently leak process memory contents (via an out-of-bounds read).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CD
C Driver · MongoDB, Inc.
1.0 before 1.30.8; 2.0 before 2.2.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-9100
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-9100
Vendor Advisory
https://jira.mongodb.org/browse/CDRIVER-6281
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