CVE-2026-41146

facil.io is a C micro-framework for web applications. Prior to commit 5128747363055201d3ecf0e29bf0a961703c9fa0, `fio_json_parse` can enter an infinite loop when it encounters a nested JSON value starting with `i` or `I`. The process spins in user space and pegs one CPU core at ~100% instead of returning a parse error. Because `iodine` vendors the same parser code, the issue also affects `iodine` when it parses attacker-controlled JSON. The smallest reproducer I found is `[i`. The quoted-value form that originally exposed the issue, `[""i`, reaches the same bug because the parser tolerates missing commas and then treats the trailing `i` as the start of another value. Commit 5128747363055201d3ecf0e29bf0a961703c9fa0 fixes the issue.

CVSS

No CVSS.

References

Link	Resource
https://github.com/boazsegev/facil.io/commit/5128747363055201d3ecf0e29bf0a961703c9fa0
https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm
https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm

Configurations

No configuration.

History

22 Apr 2026, 14:17

Type	Values Removed	Values Added
References	~~() https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm -~~	() https://github.com/boazsegev/facil.io/security/advisories/GHSA-2x79-gwq3-vxxm -

22 Apr 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-22 02:16

Updated : 2026-04-29 20:46

NVD link : CVE-2026-41146

Mitre link : CVE-2026-41146

CVE.ORG link : CVE-2026-41146

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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