devalue before 5.9.3 allows malformed null-prototype object keys to bypass parse's __proto__ rejection through
Source GCVE Database
Not known to be exploited · CVSS 6.3 Medium : upgrade to 5.9.3 when convenient.
Data as of 8 Nov 2026, 06:47 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 6.3 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 3.7 |
- Patch
- Available – fixed in 5.9.3
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 8 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 7 Nov 2026.
What to do
Upgrade devalue to 5.9.3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| sveltejsdevalue | Affected
| Fixed in
|
npmdevaluepkg:npm/devalueOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in devalue version 5.9.3 and later. Users should upgrade to version 5.9.3 or newer to remediate this vulnerability. No other mitigation actions are indicated by the vendor advisory or source data.
Description
A vulnerability in devalue versions before 5.9.3 allows attackers to bypass the __proto__ property rejection during parsing by using malformed null-prototype object keys through property-key coercion. This is an incomplete fix related to a previous advisory (GHSA-mwv9-gp5h-frr4). Although attackers can craft payloads that produce objects with a __proto__ own property, this alone does not lead to prototype pollution.