CVE-2026-123562
Devalue 5.8.0 before 5.9.3 Denial of Service via stringifyAsync Unhandled Rejection
devalue (sveltejs/devalue) 5.8.0 before 5.9.3 contains an unhandled promise rejection in stringifyAsync: when serializing multiple promises, a later promise rejecting before an earlier one settles leaves an internal rejection unhandled, even if the caller catches the returned promise. An attacker able to influence the timing or failure of serialized asynchronous values can terminate the Node.js process.
Fixes and workarounds
Fix
devalue (npm): OSV reports a fixed version 5.9.3. Check the advisory for supported release branches.
Source: OSV GHSA-x5rw-q4pp-hg5gAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| devalue sveltejs devalue
npm |
≥ 5.8.0; < 5.9.3 (affected, semver) 5.9.3 (unaffected, semver) Other versions: unaffected |
CNA: VulnCheck |
devaluedevalue
npm |
≥ 5.8.0; < 5.9.3 (affected, semver); OSV events: introduced 5.8.0; fixed 5.9.3Source events (semver)Other versions: unaffected |
OSV GHSA-x5rw-q4pp-hg5g |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 8.7 high |
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 | CNA: VulnCheck |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: VulnCheck |
| 4.0 / 8.7 high |
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/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 | NVD: [email protected] |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/sveltejs/devalue/security/advisories/GHSA-x5rw-q4pp-hg5gCNA: VulnCheck · vendor-advisory
- https://www.vulncheck.com/advisories/devalue-5.8.0-before-5.9.3-denial-of-service-via-stringifyasync-unhandled-rejectionCNA: VulnCheck · third-party-advisory
- https://github.com/sveltejs/devalue/security/advisories/GHSA-x5rw-q4pp-hg5g[email protected]
- https://www.vulncheck.com/advisories/devalue-5.8.0-before-5.9.3-denial-of-service-via-stringifyasync-unhandled-rejection[email protected]
- https://github.com/advisories/GHSA-x5rw-q4pp-hg5gOSV / GitHub Security Advisories · advisory
- https://osv.dev/vulnerability/GHSA-x5rw-q4pp-hg5gOSV / GitHub Security Advisories · osv
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