CVE-2026-18704 json
Improper Authorization in MongoDB Aggregation Framework Allows Read-Only User to Perform Unauthorized Write Operations
published 2mo ago modified 17d ago also BIT-mongodb-2026-18704 , EUVD-2026-56906
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
An issue in MongoDB Server's aggregation framework could allow an authenticated user with only read privileges to perform write operations against collections they should not be able to modify. This is due to an internal-use aggregation stage being reachable by external clients without an appropriate authorization check on its embedded operations.
Patch / fix
- bitnami mongodb 8.3.8
- MongoDB MongoDB Server 8.3.8
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/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:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | mongodb | >=8.3.0, <8.3.8 |
8.3.8 |
Affected products
- MongoDB MongoDB Server
Classification
- Weakness
-
- CWE-862 Missing Authorization
- Technology feeds
References
-
jira.mongodb.org
/browse/SERVER-129936
vendor-advisory, issue-tracking, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-18704
web
Sources
- CVE List CVE-2026-18704
- NVD CVE-2026-18704
- OSV BIT-mongodb-2026-18704
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