CVE-2026-44893
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk45th percentile - higher than 45% of all known CVEs
Summary
In the Netty library, specifically in netty-codec-haproxy prior to versions 4.1.135.Final and 4.2.15.Final, there is a memory leak vulnerability. When decoding a PP2_TYPE_SSL TLV, if the attacker sets the TLV length below 5 bytes, an IndexOutOfBoundsException is thrown and not properly handled, causing a retained slice on the pooled cumulation buffer to never be released.
Risk Assessment
The memory leak can lead to server resource exhaustion, resulting in denial of service (DoS) and potential application disruption.
Recommendation
Immediately update the Netty library to version 4.1.135.Final or 4.2.15.Final, which contain the fix for this vulnerability.
Original NVD description (English source)
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.