CVE-2026-50011
A small malicious header can claim a huge initial capacity.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, RedisArrayAggregator pre-allocates ArrayList with initial capacity equal to the RESP array element count declared in an array header. That count is taken from the wire before the corresponding child messages exist. A small malicious header can claim a huge initial capacity. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.46% probability · 39th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400, CWE-770
- Affected
- netty/netty
- Source
- security-advisories@github.com
References
- https://github.com/netty/netty/releases/tag/netty-4.1.135.FinalRelease Notes
- https://github.com/netty/netty/releases/tag/netty-4.2.15.FinalRelease Notes
- https://github.com/netty/netty/security/advisories/GHSA-5w86-c3rq-vjj7Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:37390
- https://access.redhat.com/errata/RHSA-2026:41951
- https://access.redhat.com/errata/RHSA-2026:50085
- https://access.redhat.com/errata/RHSA-2026:53644
- https://access.redhat.com/errata/RHSA-2026:53806
- https://access.redhat.com/security/cve/CVE-2026-50011
- https://bugzilla.redhat.com/show_bug.cgi?id=2488413
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-50011.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.