CVE-2026-42583
Last modified
CVE-2026-42583 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.43% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Netty | Netty | < 4.1.133 |
| Netty | Netty | >= 4.2.0, < 4.2.13 |
References
- https://github.com/netty/netty/security/advisories/GHSA-mj4r-2hfc-f8p6Exploit, Vendor Advisory
- https://github.com/netty/netty/security/advisories/GHSA-mj4r-2hfc-f8p6Exploit, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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