Is CVE-2026-42583 actively exploited?

No active exploitation of CVE-2026-42583 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-42583 be exploited remotely?

Yes. CVE-2026-42583 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-42583?

CVE-2026-42583 has a CVSS score of 7.5 (HIGH).

HOME VULNERABILITIESCVE-2026-42583

HIGH

CVE-2026-42583

CWE-400Published: May 13, 2026· Updated: May 18, 2026

7.5

CVSS v3.1

EPSS:0.04%probability of exploitation in 30 daysPercentile:12.1th

Official Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Lz4FrameDecoder allocates a ByteBuf of size decompressedLength (up to 32 MB per block) before LZ4 runs. A peer only needs a 21-byte header plus compressedLength payload bytes - 22 bytes if compressedLength == 1 - to force that allocation. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

NVD Source

Technical Analysis

CVE-2026-42583 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.