CVE-2026-123565
Devalue before 5.9.3 Quadratic Expansion Denial of Service via uneval
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
Sveltejs devalue before 5.9.3 contains a resource exhaustion vulnerability where repeated primitive strings cause quadratic expansion in the uneval function. Attackers can supply a small crafted payload that is parsed and then passed to uneval, producing a very large serialized string that exhausts memory or CPU.
| CWE | CWE-400 |
| Vendor | sveltejs |
| Product | devalue |
| Published | Nov 8, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
sveltejs / devalue
0 < 5.9.3
References
Credits
elliott-with-the-longest-name-on-github