CVE-2026-123566High· 7.5▾ TwilightSveltejs 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 …
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 41.3 · likelihood 0 · exploitation 0
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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.
devalue < 5.9.3Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Connected by shared product, vendor, weakness, or advisory.
GHSA-hx4r-w6wj-j8fgMediumdevalue: Residual sparse-array CPU amplification in uneval
CVE-2026-123565High· 7.5Devalue before 5.9.3 Quadratic Expansion Denial of Service via uneval
GHSA-mcm9-63f2-9j32Highdevalue: Repeated primitive strings cause quadratic expansion in uneval
GHSA-wf3x-273g-mvxvLowdevalue: Sparse arrays emitted by uneval cause eager allocation when evaluated
CVE-2026-123562High· 7.5Devalue 5.8.0 before 5.9.3 Denial of Service via stringifyAsync Unhandled Rejection
CVE-2026-123564High· 7.5Sveltejs devalue before 5.9.3 Memory Exhaustion via uneval Sparse Arrays