localstack · Cross-site Scripting
Source GCVE Database
Not known to be exploited · CVSS 5.4 Medium.
Data as of 26 Oct 2026, 19:44 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 22 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
PyPIlocalstackpkg:pypi/localstackOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
An issue was discovered in localstack 4.9.2 allowing attackers to execute arbitrary code via crafted content hosted on a web-accessable URL and when passed said URL in the the templateURL to the _localstack/cloudformation/deploy endpoint, the hosted content can get executed in the context of the docker container.
References
- nvd.nist.gov/vuln/detail/CVE-2025-65200 (opens in a new tab)
- github.com/localstack/localstack/pull/13293 (opens in a new tab)
- cyberroute.github.io/post/2025-12-11-localstack-hack (opens in a new tab)
- github.com/localstack/localstack/blob/aba1ee84592d76f0a88dd286fcd83b65080e31ac/localstack-core/localstack/services/cloudformation/deploy_ui.py (opens in a new tab)
- localstack.com (opens in a new tab)