What is CVE-2026-42577?

CVE-2026-42577 is a high-severity vulnerability in Netty, classified under Missing Release of Resource after Effective Lifetime. CVSS score: 7.5/10. Published 2026-05-13.

How severe is CVE-2026-42577?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Netty

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 being half-closed, leading to stale channel…

EPSS: 0.001 (16.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Netty — versions >= 4.2.0.Final, < 4.2.13.Final

Weakness classification (CWE)

CWE-772 — Missing Release of Resource after Effective Lifetime

References

security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-42577?: CVE-2026-42577 is a high-severity vulnerability in Netty, classified under Missing Release of Resource after Effective Lifetime. CVSS score: 7.5/10. Published 2026-05-13.
How severe is CVE-2026-42577?: High severity. CVSS v3 base score is 7.5 out of 10.