CVSS 4.0
5.3 mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NCVE-2026-120819 Use-after-free in Wasm JS-BSON bridge lets read-only users read 24 KiB via $accumulator
Medium (5.3) in mongodb mongodb server. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.
A memory-management flaw in the server-side JavaScript execution component of MongoDB Server can allow an authenticated user holding only read privileges to cause the server to access memory that has already been released. By submitting a specially crafted database command that runs user-supplied JavaScript, the user can cause a bounded amount of adjacent process memory to be returned in the command's result. This results in the user obtaining information they are not authorized to access. Integrity and availability are not affected.
Severity
CVSS 3.1
4.3 mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- EPSS
- 0.4% estimated probability of exploitation activity in the next 30 days; 33rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-416 Use After Free
- Published
- Modified
- Assigned by
- mongodb (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- mongodb:mongodb server
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| MongoDB Server | from 9.0.0 before 9.0.7 |