
CVE catalog
CVE-2026-42577
Netty is an asynchronous, event-driven network application framework. From 4.2.0.Final to 4.2.13.Final , Netty's epoll transport fails to detect and close TCP connections that receive a RST after bein
- Severity
- High · CVSS 7.5
- Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.41% · Oct 25, 2026
Netty is an asynchronous, event-driven network application framework. From 4.2.0.Final to 4.2.13.Final , Netty's epoll transport fails to detect and close TCP connections that receive a RST after being half-closed, leading to stale channels that are never cleaned up and, in some code paths, a 100% CPU busy-loop in the event loop thread. This vulnerability is fixed in 4.2.13.Final.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | netty | sid | 1:4.1.48-16 | vulnerable |
| Debian | netty | forky | 1:4.1.48-16 | vulnerable |
| Debian | netty | trixie | 1:4.1.48-10+deb13u1 | vulnerable |
| Debian | netty | trixie-security | 1:4.1.48-10+deb13u1 | vulnerable |
| Debian | netty | bookworm | 1:4.1.48-7+deb12u2 | vulnerable |
| Debian | netty | bookworm-security | 1:4.1.48-7+deb12u2 | vulnerable |
| Cpe | netty | Not reported | Not reported | vulnerable |
| Cpe | netty | Not reported | 4.2.13 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | netty | source | sid | (unfixed) | not yet assigned | Not reported | [1139914] |
| Debian | netty | source | forky | (unfixed) | not yet assigned | Not reported | [1139914] |
| Debian | netty | source | trixie | (unfixed) | not yet assigned | Not reported | [1139914] |
| Debian | netty | source | bookworm | (unfixed) | not yet assigned | Not reported | [1139914] |
| Cpe | netty | cpe | Not reported | 4.2.13 | Not reported | Not reported | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libnetty-java]Affected
Source package: [netty]
Details (4)
1:4.1.48-7+deb12u2· all · bookwormAffected
nvd · netty · debian · bookworm; nvd · netty · debian · 12
1:4.1.48-7+deb12u2· all · bookwormAffected
nvd · netty · debian · bookworm; nvd · netty · debian · 12
1:4.1.48-7+deb12u2· all · bookworm-securityAffected
nvd · netty · debian · bookworm; nvd · netty · debian · 12
1:4.1.48-7+deb12u2· all · bookworm-securityAffected
nvd · netty · debian · bookworm; nvd · netty · debian · 12
[Debian 13 (Trixie)]
- [libnetty-java]Affected
Source package: [netty]
Details (4)
1:4.1.48-10+deb13u1· all · trixieAffected
nvd · netty · debian · 13
1:4.1.48-10+deb13u1· all · trixieAffected
nvd · netty · debian · 13
1:4.1.48-10+deb13u1· all · trixie-securityAffected
nvd · netty · debian · 13
1:4.1.48-10+deb13u1· all · trixie-securityAffected
nvd · netty · debian · 13
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-42577]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-42577]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-42577]
- [https://security-tracker.debian.org/tracker/CVE-2026-42577]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-3046.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database]