CVE-2026-77421: JLine: ReDoS in Nano Editor Regex Search Mode
When regex search mode is enabled in the JLine3 nano editor, the user-supplied
search term is compiled directly as a Java regular expression with no timeout or
backtracking bound. A crafted pattern such as (a+)+b can hang the editor session
thread at high CPU, causing a denial of service for that session.
References
- github.com/advisories/GHSA-ph9c-7hw9-vhhw
- github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541
- github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae
- github.com/jline/jline3/pull/2012
- github.com/jline/jline3/pull/2018
- github.com/jline/jline3/releases/tag/4.3.1
- github.com/jline/jline3/releases/tag/jline-3.30.15
- github.com/jline/jline3/security/advisories/GHSA-ph9c-7hw9-vhhw
- nvd.nist.gov/vuln/detail/CVE-2026-77421
Code Behaviors & Features
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