CVE-2026-123566 (GCVE-0-2026-123566)
Vulnerability from cvelistv5 – Published: 2026-11-08 01:38 – Updated: 2026-11-09 13:56
VLAI
EPSS
VEX
Title
Devalue before 5.9.3 CPU Amplification Denial of Service via uneval
Summary
Sveltejs devalue before 5.9.3 contains a denial of service vulnerability that allows attackers to cause CPU amplification by supplying sparse arrays to uneval. Attackers who influence sparse values passed to uneval can force synchronous work proportional to the declared array length, blocking the event loop.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-09 13:56 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
VulnCheck
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/sveltejs/devalue/security/advi… | vendor-advisory |
| https://www.vulncheck.com/advisories/devalue-befo… | third-party-advisory |
Impacted products
Date Public
2026-09-18 00:00
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