7.1

CVE-2026-18688: mongodb Out-of-bounds Read

CVSS: 7.1v4.0HighAnalyzed
AliasesUBUNTU-CVE-2026-18688
Published 11-08-2026Last modified 11-08-2026
Open JSON

Vulnerability summary

CVE-2026-18688 is a high (CVSS 7.1) Out-of-bounds Read vulnerability in mongodb. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 32.9% 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
0.40%
0%100%
Low · +0.12 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 aggregation framework could allow an authenticated user to trigger an out-of-bounds memory read by providing a specially formed numeric parameter in a certain aggregation pipeline stage. This could result in a server crash (denial of service) and may potentially expose a limited amount of memory contents.

CVSS metrics

6 scores · 3 sources · 2 versions

EPSS trend

Probability

0.40%

Chance of exploitation in the next 30 days

Percentile

33%

Versus all other CVEs

30-day change

+0.12 pp

From 0.28% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.40%

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 | ≥ 7.0, < 7.0.40
Ubuntu1 product
  • mongodbAll versions (No fix recorded)

2 vendors · 3 products

References

3 links