CVE-2026-123568sveltejs devalue Prototype Pollution
NVD
Vulnerability Summary
Sveltejs devalue before 5.6.3 contains a prototype pollution vulnerability that allows attackers to alter object prototypes by supplying untrusted data to uneval. When the generated code is later evaluated, it creates objects with polluted prototypes, producing output data whose shape differs from the original input.
CVSS v4.0 Base Metrics — Score 2.1 (LOW)
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:NAttack VectorNetwork
Attack ComplexityHigh
Attack RequirementsPresent
Privileges RequiredHigh
User InteractionNone
Confidentiality (Vulnerable System)Low
Integrity (Vulnerable System)Low
Availability (Vulnerable System)None
Confidentiality (Subsequent System)Low
Integrity (Subsequent System)Low
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 4.4)
CVSS v3.1 Base Metrics — Score 4.4 (MEDIUM)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:NAttack VectorNetwork
Attack ComplexityHigh
Privileges RequiredHigh
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone
Affected & Patched Versions
- sveltejs devalue < 5.6.3
- sveltejs devalue 5.6.3
What to do
Fix it during your normal patch cycle. No exploitation is confirmed yet.
- Check whether you run sveltejs devalue and which version.
- Update to a patched version listed above, then confirm the new version.
Timeline
- Nov 8, 2026Published
- Nov 12, 2026Record last modified
Score, severity and exploitation changes are tracked from the day Watchtower started logging them.
Get notified about new sveltejs devalue CVEsYou are reading CVE-2026-123568. Get an email when KEV listings, exploits or new CVEs match your stack.
Set up CVE alertsMore sveltejs devalue CVEs
External References
Data last checked: Nov 14, 2026 02:13 UTC