CVE-2026-85730
The parser then hangs indefinitely and can consume a service's processing capacity when an application parses attacker-controlled TOML.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.2 HIGHCVSS: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/M
- EPSS
- 0.38% probability · 32th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-606, CWE-835
- Source
- security-advisories@github.com
References
- https://github.com/squirrelchat/smol-toml/commit/30f5c367d946b695f379b5d4f0946b2f0a0a8c2f
- https://github.com/squirrelchat/smol-toml/releases/tag/v1.7.1
- https://github.com/squirrelchat/smol-toml/security/advisories/GHSA-7w5x-hrqm-74c2
- https://medium.com/@ravindu.lakmina1/seven-bytes-that-freeze-a-node-js-server-forever-the-story-of-cve-2026-85730-3213328b38f0
- https://github.com/squirrelchat/smol-toml/security/advisories/GHSA-7w5x-hrqm-74c2
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.