CVE-2026-123564: high-severity vulnerability in sveltejs devalue
Sveltejs devalue before 5.9.3 Memory Exhaustion via uneval Sparse Arrays
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.3%
Sveltejs devalue from 1.0.0 before 5.9.3 contains a memory exhaustion flaw in uneval, whose generated code for sparse arrays allocates memory proportional to the array's declared length when evaluated. Attackers who can influence a very large sparse array serialized by an application can exhaust memory in the browser or runtime evaluating the output.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
sveltejs · devalueRelated CVEs — sveltejs devalue
In the same product, most dangerous first.
CVE-2026-92708HIGHdevalue: Cross-request process memory disclosure in devalue when `stringify` / `uneval` serialize Node BuffersEPSS 0.7%CVE-2026-22775HIGHdevalue vulnerable to denial of service due to memory/CPU exhaustion in devalue.parseEPSS 0.6%CVE-2026-22774HIGHdevalue vulnerable to denial of service due to memory exhaustion in devalue.parseEPSS 0.6%CVE-2026-81176MEDIUMSvelte devalue: DoS via malformed inputEPSS 0.5%CVE-2026-30226MEDIUMdevalue has prototype pollution in devalue.parse and devalue.unflattenEPSS 0.5%CVE-2026-42570HIGHSvelte devalue: DoS via sparse array deserializationEPSS 0.4%