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.
CVE-2026-30226
HIGHNVD 7.57.5
EchelonGraph scoreLOW confidence
This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: nvd
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(low)
- EG Risk
- 38(Track)EG Risk 38/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity75% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 30%
- KEV
- Not listed
Published
March 11, 2026
Last Modified
June 17, 2026
References (1)
- security-advisories@githubhttps://github.com/sveltejs/devalue/security/advisories/GHSA-cfw5-2vxh-hr84
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 1× in last 7d / 1× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-27 13:41 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-1321
Frequently asked(5)
What is CVE-2026-30226?
CVE-2026-30226 is a high vulnerability published on March 11, 2026. 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…
When was CVE-2026-30226 disclosed?
CVE-2026-30226 was first published in the National Vulnerability Database on March 11, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-30226 actively exploited?
CVE-2026-30226 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 70.1% of all scored CVEs.
What is the CVSS score of CVE-2026-30226?
CVE-2026-30226 has a CVSS v3 base score of 7.5 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-30226?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-30226, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-30226
Is Your Infrastructure Affected by CVE-2026-30226?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.