CVE-2026-8336 json
Post-authentication use-after-free error in $_internalJsEmit and mapreduce commands
published 2026-05-13 5 mo ago modified 2026-10-26 13 d ago also BIT-mongodb-2026-8336 , EUVD-2026-29893
- cvss
- 7.5
- 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 17%
- public exploits
- 0
- none known
Summary
After invoking $_internalJsEmit, which is not intended to be directly accessible, or mapreduce command’s map function in a certain way, an authenticated user can subsequently crash mongod when the server-side JavaScript engine (through $where, $function, mapreduce reduce stage, etc.) is used also in a specific way, resulting in a post-authentication denial-of-service.
This issue impacts MongoDB Server v8.2 versions prior to 8.2.9 and v8.3 versions prior to 8.3.2.
Patch / fix
- bitnami mongodb 8.2.9, 8.3.2
- MongoDB, Inc. MongoDB Server 8.2.9, 8.3.2
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 5 mo ago
Exploit prediction
0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.7 | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/AU:N/R:A/V:D/RE:M/U:Red |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 7.7 | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/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:N/R:A/V:D/RE:M/U:Red |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | mongodb | >=8.2.0, <8.2.9 >=8.3.0, <8.3.2 |
8.2.9 8.3.2 |
Affected products
- MongoDB, Inc. MongoDB Server
Classification
- Weakness
-
- CWE-416 Use After Free
- Technology feeds
References
-
jira.mongodb.org
/browse/SERVER-121610
issue-tracking, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-8336
web
Sources
- CVE List CVE-2026-8336
- NVD CVE-2026-8336
- OSV BIT-mongodb-2026-8336
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.