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Vulnerability Details :

CVE-2026-4269

Summary
Assigner-AMZN
Assigner Org ID-ff89ba41-3aa1-4d27-914a-91399e9639e5
Published At-16 Mar, 2026 | 18:03
Updated At-16 Mar, 2026 | 18:12
Rejected At-
Credits

Improper S3 ownership verification in Bedrock AgentCore Starter Toolkit

A missing S3 ownership verification in the Bedrock AgentCore Starter Toolkit before version v0.1.13 may allow a remote actor to inject code during the build process, leading to code execution in the AgentCore Runtime. This issue only affects users of the Bedrock AgentCore Starter Toolkit before version v0.1.13 who build or have built the Toolkit after September 24, 2025. Any users on a version >=v0.1.13, and any users on previous versions who built the toolkit before September 24, 2025 are not affected. To remediate this issue, customers should upgrade to version v0.1.13.

Vendors
-
Not available
Products
-
Metrics (CVSS)
VersionBase scoreBase severityVector
Weaknesses
Attack Patterns
Solution/Workaround
References
HyperlinkResource Type
EPSS History
Score
Latest Score
-
N/A
No data available for selected date range
Percentile
Latest Percentile
-
N/A
No data available for selected date range
Stakeholder-Specific Vulnerability Categorization (SSVC)
▼Common Vulnerabilities and Exposures (CVE)
cve.org
Assigner:AMZN
Assigner Org ID:ff89ba41-3aa1-4d27-914a-91399e9639e5
Published At:16 Mar, 2026 | 18:03
Updated At:16 Mar, 2026 | 18:12
Rejected At:
▼CVE Numbering Authority (CNA)
Improper S3 ownership verification in Bedrock AgentCore Starter Toolkit

A missing S3 ownership verification in the Bedrock AgentCore Starter Toolkit before version v0.1.13 may allow a remote actor to inject code during the build process, leading to code execution in the AgentCore Runtime. This issue only affects users of the Bedrock AgentCore Starter Toolkit before version v0.1.13 who build or have built the Toolkit after September 24, 2025. Any users on a version >=v0.1.13, and any users on previous versions who built the toolkit before September 24, 2025 are not affected. To remediate this issue, customers should upgrade to version v0.1.13.

Affected Products
Vendor
AWS
Product
Bedrock AgentCore Starter Toolkit
Default Status
unaffected
Versions
Affected
  • From 0.1.0 before 0.1.13 (custom)
Problem Types
TypeCWE IDDescription
CWECWE-340CWE-340 Generation of Predictable Numbers or Identifiers
CWECWE-283CWE-283 Unverified Ownership
Type: CWE
CWE ID: CWE-340
Description: CWE-340 Generation of Predictable Numbers or Identifiers
Type: CWE
CWE ID: CWE-283
Description: CWE-283 Unverified Ownership
Metrics
VersionBase scoreBase severityVector
3.17.5HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
4.05.8MEDIUM
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H
Version: 3.1
Base score: 7.5
Base severity: HIGH
Vector:
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Version: 4.0
Base score: 5.8
Base severity: MEDIUM
Vector:
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H
Metrics Other Info
Impacts
CAPEC IDDescription
CAPEC-253CAPEC-253 Remote Code Inclusion
CAPEC ID: CAPEC-253
Description: CAPEC-253 Remote Code Inclusion
Solutions
Configurations
Workarounds
Exploits
Credits
Timeline
EventDate
Replaced By
Rejected Reason
References
HyperlinkResource
https://github.com/aws/bedrock-agentcore-starter-toolkit/releases/tag/v0.1.13
patch
https://aws.amazon.com/security/security-bulletins/2026-008-AWS/
vendor-advisory
Hyperlink: https://github.com/aws/bedrock-agentcore-starter-toolkit/releases/tag/v0.1.13
Resource:
patch
Hyperlink: https://aws.amazon.com/security/security-bulletins/2026-008-AWS/
Resource:
vendor-advisory
▼Authorized Data Publishers (ADP)
CISA ADP Vulnrichment
Affected Products
Metrics
VersionBase scoreBase severityVector
Metrics Other Info
Impacts
CAPEC IDDescription
Solutions
Configurations
Workarounds
Exploits
Credits
Timeline
EventDate
Replaced By
Rejected Reason
References
HyperlinkResource
Information is not available yet
▼National Vulnerability Database (NVD)
nvd.nist.gov
Source:ff89ba41-3aa1-4d27-914a-91399e9639e5
Published At:16 Mar, 2026 | 18:16
Updated At:11 May, 2026 | 14:34

A missing S3 ownership verification in the Bedrock AgentCore Starter Toolkit before version v0.1.13 may allow a remote actor to inject code during the build process, leading to code execution in the AgentCore Runtime. This issue only affects users of the Bedrock AgentCore Starter Toolkit before version v0.1.13 who build or have built the Toolkit after September 24, 2025. Any users on a version >=v0.1.13, and any users on previous versions who built the toolkit before September 24, 2025 are not affected. To remediate this issue, customers should upgrade to version v0.1.13.

CISA Catalog
Date AddedDue DateVulnerability NameRequired Action
N/A
Date Added: N/A
Due Date: N/A
Vulnerability Name: N/A
Required Action: N/A
Metrics
TypeVersionBase scoreBase severityVector
Secondary4.05.8MEDIUM
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/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
Secondary3.17.5HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Type: Secondary
Version: 4.0
Base score: 5.8
Base severity: MEDIUM
Vector:
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/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
Type: Secondary
Version: 3.1
Base score: 7.5
Base severity: HIGH
Vector:
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CPE Matches
amazon
amazon
>>bedrock_agentcore_starter_toolkit>>Versions before 0.1.13(exclusive)
cpe:2.3:a:amazon:bedrock_agentcore_starter_toolkit:*:*:*:*:*:python:*:*
Weaknesses
CWE IDTypeSource
CWE-283Secondaryff89ba41-3aa1-4d27-914a-91399e9639e5
CWE-340Secondaryff89ba41-3aa1-4d27-914a-91399e9639e5
CWE ID: CWE-283
Type: Secondary
Source: ff89ba41-3aa1-4d27-914a-91399e9639e5
CWE ID: CWE-340
Type: Secondary
Source: ff89ba41-3aa1-4d27-914a-91399e9639e5
Evaluator Description
Evaluator Impact

Evaluator Solution

Vendor Statements
References
HyperlinkSourceResource
https://aws.amazon.com/security/security-bulletins/2026-008-AWS/ff89ba41-3aa1-4d27-914a-91399e9639e5
Vendor Advisory
https://github.com/aws/bedrock-agentcore-starter-toolkit/releases/tag/v0.1.13ff89ba41-3aa1-4d27-914a-91399e9639e5
Release Notes
Hyperlink: https://aws.amazon.com/security/security-bulletins/2026-008-AWS/
Source: ff89ba41-3aa1-4d27-914a-91399e9639e5
Resource:
Vendor Advisory
Hyperlink: https://github.com/aws/bedrock-agentcore-starter-toolkit/releases/tag/v0.1.13
Source: ff89ba41-3aa1-4d27-914a-91399e9639e5
Resource:
Release Notes

Change History

0
Information is not available yet

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