8.7

CVE-2026-18697: mongodb Reachable Assertion

CVSS: 8.7v4.0HighAnalyzed
AliasesUBUNTU-CVE-2026-18697
Published 11-08-2026Last modified 11-08-2026

Vulnerability summary

CVE-2026-18697 is a high (CVSS 8.7) Reachable Assertion vulnerability in mongodb. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 37.1% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.7/10
010
High · v4.0 (CVE.org)
EPSS score
0.44%
0%100%
Low · +0.11 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 unauthenticated party to cause a mongos (router) process to terminate unexpectedly by submitting a specially formed aggregation command. This could result in a denial of service, disrupting client connections routed through the affected mongos instance.

CVSS metrics

6 scores · 3 sources · 2 versions

EPSS trend

Probability

0.44%

Chance of exploitation in the next 30 days

Percentile

37%

Versus all other CVEs

30-day change

+0.11 pp

From 0.33% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.44%

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