CVE-2026-116539: high-severity vulnerability in netty-tcnative
Netty netty-tcnative before 2.0.84.Final Heap Buffer Overflow via OpenSSL BIO
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.4%
Netty netty-tcnative before 2.0.84.Final contains a heap buffer overflow vulnerability in the tcn_write_to_bytebuffer BIO callback caused by failing to wrap the non-application ring buffer write index. Remote TLS peers can drive handshake, renegotiation, or post-handshake messages into this buffer, triggering an out-of-bounds memcpy that crashes the JVM process.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Related CVEs — netty-tcnative
In the same product, most dangerous first.
CVE-2026-116541HIGHnetty-tcnative before 2.0.84.Final Denial of Service via BIO Write OvercountEPSS 0.5%CVE-2026-116540HIGHnetty-tcnative 2.0.66.Final before 2.0.84.Final Use-After-Free in Session Ticket CallbackEPSS 0.5%CVE-2026-116542MEDIUMNetty netty-tcnative before 2.0.84.Final SNI Hostname Spoofing via Modified UTF-8 DecodingEPSS 0.2%
References
https://github.com/netty/netty-tcnativehttps://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/ssl.c#L199https://github.com/netty/netty-tcnative/commit/92dd66fd1243d85c05a61288f96367a70260b6b8https://github.com/netty/netty-tcnative/releases/tag/netty-tcnative-parent-2.0.84.Finalhttps://github.com/netty/netty-tcnative/security/advisories/GHSA-gf9q-9mg7-g5qhhttps://www.vulncheck.com/advisories/netty-netty-tcnative-before-2.0.84-final-heap-buffer-overflow-via-openssl-bio