CVSS 4.0
6.3 mediumCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NCVE-2026-30226
Medium (6.3) in svelte devalue. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in devalue 5.6.4.
Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. In devalue v5.6.3 and earlier, devalue.parse and devalue.unflatten were susceptible to prototype pollution via maliciously crafted payloads. Successful exploitation could lead to Denial of Service (DoS) or type confusion. This vulnerability is fixed in 5.6.4.
Severity
CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 35% of CVEs (scores of 2026-10-31)
- CWE
- CWE-1321
- Published
- Modified
- Record from
- the NVD, synced
Affected
- svelte:devalue
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-cfw5-2vxh-hr84 | npm | devalue | <5.6.4 | 5.6.4 |