Description
Jawn is an open source JSON parser. Prior to 1.7.0, Jawn's AsyncParser can perform quadratic work when a single JSON token is delivered across many small chunks because each absorb call rescans the incomplete token from the start. A remote attacker who controls untrusted JSON input and its chunk sizes can exhaust CPU resources and cause denial of service in applications using AsyncParser. This issue is fixed in version 1.7.0.
References3
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: 55 · as of 9 November 2026
- CWE
- CWE-400CWE-407
Could this be exploited in your environment?
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