Vulnerability in Netty

CVE-2026-44893

Netty is a network application framework for development of protocol servers and clients. In netty-codec-haproxy prior to versions 4.1.135.Final and 4.2.15.Final, when decoding a PP2_TYPE_SSL TLV, HAProxyMessage.readNextTLV() first calls `header.retainedSlice(header.readerIndex(), length)` and only then reads the 1-byte client field and 4-byte verify field. If the attacker sets the TLV length below 5, the subsequent readByte/readInt throws IndexOutOfBoundsException. HAProxyMessageDecoder only catches HAProxyProtocolException around this call, so the IOOBE propagates and the retained slice on the pooled cumulation buffer is never released. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

EPSS: 0.006 (47.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

  • Netty — versions >= 4.2.0.Final, < 4.2.15.Final, < 4.1.135.Final

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-44893?
CVE-2026-44893 is a high-severity vulnerability in Netty, classified under CWE-703. CVSS score: 7.5/10. Published 2026-06-12.
How severe is CVE-2026-44893?
High severity. CVSS v3 base score is 7.5 out of 10.