CVE-2026-42579

⚠️ high

Summary

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

CVSS Score

7.5

High

EPSS Score

0.0

Exploit Probability

Published Date

2026-05-13

First Seen: 2026-05-17

📊 Relative Risk Intelligence

This CVE is Moderate Risk - more severe than 69.0% of all 327,350 vulnerabilities in our database.

#101,599

Above average severity

Severity Percentile

🎯 CISA SSVC Assessment Updated: May 18, 2026

🔍 Exploitation Status

Poc

Proof-of-concept available

⚙️ Automatable

YES

Can be exploited automatically

💥 Technical Impact

Partial

Limited system impact

SSVC data provided by CISA

Last Modified 2026-05-18

Source NVD 🔗

CVSS Vector 3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CWE IDs (Weakness Types)

CWE-20 CWE-400 CWE-626

📦 Affected Products 2

Vendor	Product	Status	Affected Versions
netty	netty	Affected	< 4.1.133
netty	netty	Affected	> 4.2.0 < 4.2.13

🔗 References 1

https://github.com/netty/netty/security/advisories/G...

Exploit Mitigation Vendor Advisory

🔗 Related CVEs 6

CVE ID	Severity	CVSS	EPSS	Summary	Published
CVE-2026-42577	⚠️ high	7.5	0.1	Netty is an asynchronous, event-driven network application framework. From 4.2.0.Final to 4.2.13.Final , Netty's epoll t...	2026-05-13
CVE-2026-42578	⚠️ high	7.5	0.0	Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's H...	2026-05-13
CVE-2026-42580	🔶 medium	6.5	0.0	Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's c...	2026-05-13
CVE-2026-42581	🔶 medium	5.8	0.0	Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjec...	2026-05-13
CVE-2026-42582	⚠️ high	7.5	0.0	Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final, when decoding header blocks...	2026-05-13
CVE-2026-42583	⚠️ high	7.5	0.0	Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Lz4FrameD...	2026-05-13

These CVEs affect the same products