CVE-2025-58057: netty — Exploit & Fix

Description

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In netty-codec-compression versions 4.1.124.Final and below, and netty-codec versions 4.2.4.Final and below, when supplied with specially crafted input, BrotliDecoder and certain other decompression decoders will allocate a large number of reachable byte buffers, which can lead to denial of service. BrotliDecoder.decompress has no limit in how often it calls pull, decompressing data 64K bytes at a time. The buffers are saved in the output list, and remain reachable until OOM is hit. This is fixed in versions 4.1.125.Final of netty-codec and 4.2.5.Final of netty-codec-compression.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-409 CWE-409

Affected Products

Vendor	Product	Versions
netty	netty	< 4.1.125
netty	netty	4.2.0 — 4.2.5

References

Advisories & Patches

https://github.com/netty/netty/commit/9d804c54ce962408ae6418255a83a13924f7145d https://github.com/netty/netty/security/advisories/GHSA-3p8m-j85q-pgmj

Exploits

https://github.com/netty/netty/security/advisories/GHSA-3p8m-j85q-pgmj

Frequently Asked Questions

What is CVE-2025-58057? +

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In netty-codec-compression versions 4.1.124.Final and below, and netty-codec versions 4.2.4.Final and below, when supplied with specially crafted input, BrotliDecoder and certain other decompression decoders will allocate a large number of reachable byte buffers, which can lead to denial of service. BrotliDecoder.decompress has no limit in how often it calls pull, decompressing data 64K bytes at a time. The buffers are saved in the output list, and remain reachable until OOM is hit. This is fixed in versions 4.1.125.Final of netty-codec and 4.2.5.Final of netty-codec-compression. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2025-58057? +

CVE-2025-58057 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-58057? +

CVE-2025-58057 affects products from netty, specifically: netty. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-58057? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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