CVE-2026-11933: Post-authentication use-after-free in server-side JavaScript BSON-to-array conversion
Vulnerability summary
CVE-2026-11933 is a high (CVSS 8.8) Out-of-bounds Write vulnerability in mongodb. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 32.4% of scored vulnerabilities.
Not severe (CVSS 8.7, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 12-06-2026PublishedVulnerability first disclosed.
- 13-06-2026Last modifiedVulnerability information updated.
Description
A use-after-free vulnerability exists in MongoDB Server's server-side JavaScript engine when converting BSON documents to JavaScript arrays. An authenticated user with read privileges who is able to run server-side JavaScript (for example, via $where or $function) can cause the server to access memory that has already been freed. This may result in disclosure of information from the mongod process memory or a denial of service through a server crash.
CVSS metrics
6 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated8.7HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- NVDNIST8.7HighCVSS:4.0/AV:N/AC:L/AT:N/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:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST8.8HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.38%
Chance of exploitation in the next 30 days
Percentile
32%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.38% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
- CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Affected systems
Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Mongodb1 product
- mongodb≥ 8.3.0, ≤ 8.3.3 | ≥ 8.2.0, ≤ 8.2.10 | ≥ 8.0.0, ≤ 8.0.25 | ≥ 7.0.0, ≤ 7.0.36 | ≥ 6.0, ≤ 6.0.28 | ≥ 5.0, ≤ 5.0.33 | ≥ 4.4.0, ≤ 4.4.30 | ≥ 4.4.0, < 4.4.31 | ≥ 5.0.0, < 5.0.34 | ≥ 6.0.0, < 6.0.29 | ≥ 7.0.0, < 7.0.37 | ≥ 8.0.0, < 8.0.26 | ≥ 8.2.0, < 8.2.11 | ≥ 8.3.0, < 8.3.4
Ubuntu1 product
- mongodbAll versions (No fix recorded)
2 vendors · 2 products