Public vulnerability disclosure

CVE-2026-120816

System collection contents readable through a database change stream with showSystemEvents

publishedCWE-863

A user with basic read-tier database privileges can use an option on a server-side data-change notification feature to receive the contents of certain restricted internal collections that the same user is refused on a direct read. The privilege check for the notification feature is derived only from the target namespace and does not account for the option, so no additional permission is required. This may result in unintended access to data stored in those internal collections.

Technical severity2.3 lowCVSS 4.0 · CNA: mongodb
Published2026-11-10Source updated 2026-11-13
Collected2026-11-133 attributed sources

Fixes and workarounds

No remediation reported in collected sources.

Missing remediation information is not evidence that no patch exists.

Affected products and versions

Affected products, source version ranges and reporting authorities
ProductVersionsAuthority
MongoDB Server
MongoDB
≥ 9.0.0; < 9.0.7 (affected, semver)
≥ 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

CVSS scores, vectors and reporting authorities
Version / scoreVectorAuthority
4.0 / 2.3
low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NCNA: mongodb
3.1 / 4.3
medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:NCNA: mongodb
4.0 / 2.3
low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/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:XNVD: [email protected]
3.1 / 4.3
medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:NNVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

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