CVE-2026-120818
Use-After-Free in MongoDB Server JavaScript Support for Aggregation Leads to Information Disclosure
A use-after-free weakness in MongoDB Server's server-side JavaScript support for aggregation may allow a stale reference to previously freed process memory to be read and returned. An authenticated user with minimal or no assigned roles can trigger this condition over the normal network protocol by submitting a single crafted aggregation request, with no additional privileges or non-default configuration. Successful triggering this issue may result in adjacent process memory contents being returned, including data that undermines memory-layout randomization, and may in some cases affect server availability.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| MongoDB Server MongoDB |
≥ 8.3.0; < 8.3.16 (affected, semver) ≥ 8.0.0; < 8.0.37 (affected, semver) ≥ 7.0.0; < 7.0.48 (affected, semver) Other versions: unaffected |
CNA: mongodb |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 7.1 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N | CNA: mongodb |
| 3.1 / 7.1 high |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L | CNA: mongodb |
| 4.0 / 7.1 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD: [email protected] |
| 3.1 / 7.1 high |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
For agents and automation
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