8.6

CVE-2026-18830: aws amazon bedrock agentcore harness

CVSS: 8.6v4.0HighAwaiting analysis
Published 04-08-2026Last modified 11-10-2026
Open JSON

Vulnerability summary

CVE-2026-18830 is a high (CVSS 8.6) vulnerability in aws amazon bedrock agentcore harness. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 42% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.6/10
010
High · v4.0 (CVE.org)
EPSS score
0.51%
0%100%
Low · -0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 04-08-2026
    PublishedVulnerability first disclosed.
  2. 11-10-2026
    Last modifiedVulnerability information updated.

Description

Insufficient input validation in Amazon Bedrock AgentCore harness might allow an authenticated remote user to execute configured tools bypassing model invocation and security controls via crafted content blocks in conversation messages. AWS has addressed this issue. No customer action is required.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.51%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

-0.02 pp

From 0.53% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.51%

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

Aws1 product

1 vendor · 1 product

References

1 links