Description
smol-toml is a small, fast, and correct TOML parser and serializer. Prior to 1.7.1, parse() can enter an infinite loop when a value inside an array or inline table is followed by a comment with no trailing newline. In src/util.ts, skipUntil() calls indexOfNewline(), receives -1 at the end of input, and resets the cursor to the beginning of the string instead of leaving the structure scan. The parser then hangs indefinitely and can consume a service's processing capacity when an application parses attacker-controlled TOML. This issue is fixed in version 1.7.1.
References5
- github.com/squirrelchat/smol-toml/commit/30f5c367d946b695f379b5…
- github.com/squirrelchat/smol-toml/releases/tag/v1.7.1
- github.com/squirrelchat/smol-toml/security/advisories/GHSA-7w5x…
- medium.com/@ravindu.lakmina1/seven-bytes-that-freeze-a-node-js-…
- github.com/squirrelchat/smol-toml/security/advisories/GHSA-7w5x…
Metrics
- CVSS 4.0
-
8.2
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/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 - EPSS — exploit probability
- 1% percentile: 45 · as of 4 November 2026
- CWE
- CWE-606CWE-835
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