CVE-2026-120809
Last modified
CVE-2026-120809 is a medium-severity vulnerability rated 6.8/10 on the CVSS scale. A use-after-free read issue exists in MongoDB’s SBE (Slot-Based Execution) engine when processing aggregation pipelines with $unwind on time-series collections. An internal error in state-preservation logic can cause a value still referenced by downstream stages to have its underlying memory freed prematurely. EPSS estimates a 0.37% chance of exploitation in the next 30 days.
Description
A use-after-free read issue exists in MongoDB’s SBE (Slot-Based Execution) engine when processing aggregation pipelines with $unwind on time-series collections. An internal error in state-preservation logic can cause a value still referenced by downstream stages to have its underlying memory freed prematurely. An authenticated user can craft an aggregation pipeline under specific conditions to trigger this condition, potentially reading recycled server heap memory in query results or crashing the server. This issue is only triggerable when a non-default server parameter related to the SBE engine is enabled.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| MongoDB | MongoDB Server | >= 9.0.0, < 9.0.7; >= 8.3.0, < 8.3.16; >= 8.0.0, < 8.0.37 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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