CVE-2026-30226
devalue has prototype pollution in devalue.parse and devalue.unflatten
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
devalue has prototype pollution in devalue.parse and devalue.unflatten
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.
- Record
CVE-2026-30226- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
EUVDEUVD-2026-11253
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.
- Record
EUVD-2026-11253- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-cfw5-2vxh-hr84
devalue has prototype pollution in devalue.parse and devalue.unflatten
In devalue v5.6.3, 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.
- Record
GHSA-cfw5-2vxh-hr84- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-30226- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSV
devalue has prototype pollution in devalue.parse and devalue.unflatten
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.
- Record
CVE-2026-30226- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSVGHSA-cfw5-2vxh-hr84
devalue has prototype pollution in devalue.parse and devalue.unflatten
In devalue v5.6.3, 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.
- Record
GHSA-cfw5-2vxh-hr84- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSVCLSA-2026-1786357331 No score
TuxCare security update for devalue (5 CVEs)
TuxCare rebuilt devalue to address 5 CVEs. Fixed in 4.3.2-tuxcare.1.
- Record
CLSA-2026-1786357331- Updated
- 2026-11-02
OSVROOT-APP-NPM-CVE-2026-30226 No score
CVE-2026-30226 in @rootio/devalue - Patched by Root
Root has patched CVE-2026-30226 in the @rootio/devalue package for Root:npm. Multiple fixed versions available.
- Record
ROOT-APP-NPM-CVE-2026-30226- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
devaluenpm |
before 5.6.4 | 5.6.4 |
devalueTuxCare:npm From an advisory covering 2 CVEs |
4.3.2-tuxcare.0 up to 4.3.2-tuxcare.1, plus listed versions 4.3.2 |
4.3.2-tuxcare.1 |
@rootio/devalueRoot:npm |
before 4.3.3-root.io.1 | 4.3.3-root.io.1 |
devalueRoot:npm |
before 4.3.3-aikido.1 | 4.3.3-aikido.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-30226 is a medium vulnerability (CVSS 6.3) in Svelte Devalue, published March 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.47%, the 40th percentile. Fixed in devalue 5.6.4.