Service interruption via unbounded recursive TOML parsing
Published Sep 22, 2026 · Updated Sep 22, 2026
Uncontrolled recursion in js-toml before 1.1.3 allows attackers to interrupt services by supplying deeply nested TOML. The load() parser and interpreter impose no nesting or dotted-key depth bound, allowing recursive calls to exhaust the V8 stack and emit a raw RangeError. Impact requires a consuming application to parse attacker-controlled TOML and mishandle non-SyntaxParseError exceptions; the result is a catchable worker or process termination without data disclosure or modification.
Summary
What happened
Uncontrolled recursion in js-toml before 1.1.3 allows attackers to interrupt services by supplying deeply nested TOML. The load() parser and interpreter impose no nesting or dotted-key depth bound, allowing recursive calls to exhaust the V8 stack and emit a raw RangeError. Impact requires a consuming application to parse attacker-controlled TOML and mishandle non-SyntaxParseError exceptions; the result is a catchable worker or process termination without data disclosure or modification.
The record
- CVE
- CVE-2026-63386
- Published
- Sep 22, 2026
- Updated
- Sep 22, 2026
- Vendor
- sunnyadn
- Product
- js-toml
- Classifications
- CWE-674, T1499.004
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 22, 2026CVE publishedPublication date reported by the CVE source.
- Sep 22, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 1.1.3
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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