Vulnerability · Published Aug 11, 2026 · Assigned by mongodb
CVE-2026-18693Out-of-Bounds Read/Write in MongoDB Timeseries Bucket Handling Leads to Denial of Service and Potential Memory Disclosure
High 7.6
In plain English
A high-severity out-of-bounds write in MongoDB Server from MongoDB. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities).
Official description
An issue in MongoDB Server's handling of timeseries collections could allow an authenticated user with write privileges to cause an internal data structure to become inconsistent through certain document insertions. A subsequent insert into the affected bucket could then result in the server accessing memory outside its intended bounds, potentially causing a server crash (denial of service), exposure of limited memory contents, or memory corruption.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| MongoDB | MongoDB Server | 8.3.0 – before 8.3.88.0 – before 8.0.297.0 – before 7.0.40 |
Weakness: CWE-787 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H