Description
flatted is a circular JSON parser. Prior to 3.4.0, flatted's parse() function uses a recursive revive() phase to resolve circular references in deserialized JSON. When given a crafted payload with deeply nested or self-referential $ indices, the recursion depth is unbounded, causing a stack overflow that crashes the Node.js process. This vulnerability is fixed in 3.4.0.
Affected products
webreflection: flatted
References10
- github.com/WebReflection/flatted/security/advisories/GHSA-25h7-… ExploitPatchVendor Advisory
- github.com/WebReflection/flatted/security/advisories/GHSA-25h7-… ExploitPatchVendor Advisory
- github.com/WebReflection/flatted/commit/7eb65d857e1a40de11c4746… Patch
- github.com/WebReflection/flatted/pull/88 Issue TrackingPatch
- access.redhat.com/errata/RHSA-2026:13826
- access.redhat.com/errata/RHSA-2026:21772
- access.redhat.com/errata/RHSA-2026:34342
- access.redhat.com/errata/RHSA-2026:36651
- access.redhat.com/errata/RHSA-2026:40118
- access.redhat.com/errata/RHSA-2026:40945
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 60 · as of 12 November 2026
- CWE
- CWE-674CWE-770
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