7.1

CVE-2026-18711: mongodb Use After Free

CVSS: 7.1v4.0HighAnalyzed
AliasesUBUNTU-CVE-2026-18711
Published 11-08-2026Last modified 11-08-2026
Open JSON

Vulnerability summary

CVE-2026-18711 is a high (CVSS 7.1) Use After Free vulnerability in mongodb. EPSS estimates a 0.49% chance of exploitation in the next 30 days, higher than 41.4% of scored vulnerabilities.

Overall risk
28/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.1/10
010
High · v4.0 (CVE.org)
EPSS score
0.49%
0%100%
Low · +0.22 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 11-08-2026
    PublishedVulnerability first disclosed.
  2. 11-08-2026
    Last modifiedVulnerability information updated.

Description

An issue in MongoDB Server's query execution engine could allow an authenticated user with read and write privileges to cause an internal reference to be used after the underlying memory has been freed, when running certain queries against time-series collections. This could result in a server crash or disclosure of freed memory contents within query results.

CVSS metrics

6 scores · 3 sources · 2 versions

EPSS trend

Probability

0.49%

Chance of exploitation in the next 30 days

Percentile

41%

Versus all other CVEs

30-day change

+0.22 pp

From 0.27% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.49%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Mongodb2 products
  • mongodb≥ 7.0.0, ≤ 7.0.40 | ≥ 8.0.0, < 8.0.29 | ≥ 8.2.0, ≤ 8.2.12 | ≥ 8.3.0, < 8.3.8 | 9.0.0:alpha0 | 9.0.0:alpha1 | 9.1.0:alpha0
  • mongodb server≥ 8.3.0, < 8.3.8 | ≥ 8.0, < 8.0.29
Ubuntu1 product
  • mongodbAll versions (No fix recorded)

2 vendors · 3 products

References

3 links