High severity · published Apr 2, 2026
CVE-2026-5429
Kiro IDE Webview Cross-Site Scripting via Workspace Color Theme
7.8
CVSS
0.2%
EPSS
No
On KEV
Description
Unsanitized input during web page generation in the Kiro Agent webview in Kiro IDE before version 0.8.140 allows a remote unauthenticated threat actor to execute arbitrary code via a potentially damaging crafted color theme name when a local user opens the workspace. This issue requires the user to trust the workspace when prompted.
To remediate this issue, users should upgrade to version 0.8.140.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KI
Kiro IDE · AWS
0.1 before 0.8.140 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-5429
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-5429
aws.amazon.com
https://aws.amazon.com/security/security-bulletins/2026-012-aws/
kiro.dev
https://kiro.dev/changelog/ide/0-8/#patch-0-8-140
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