CVE-2026-116539
Netty netty-tcnative before 2.0.84.Final Heap Buffer Overflow via OpenSSL BIO
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-787 |
| Vendor | netty |
| Product | netty-tcnative |
| Published | Oct 26, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
netty / netty-tcnative
0 < 2.0.84.Final
netty / netty-tcnative-boringssl-static
0 < 2.0.84.Final
References
github.com: https://github.com/netty/netty-tcnative/security/advisories/GHSA-gf9q-9mg7-g5qh github.com: https://github.com/netty/netty-tcnative/commit/92dd66fd1243d85c05a61288f96367a70260b6b8 github.com: https://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/ssl.c#L199 github.com: https://github.com/netty/netty-tcnative/releases/tag/netty-tcnative-parent-2.0.84.Final github.com: https://github.com/netty/netty-tcnative vulncheck.com: https://www.vulncheck.com/advisories/netty-netty-tcnative-before-2.0.84-final-heap-buffer-overflow-via-openssl-bio
Credits
Yu Bao, PayPal Cyber Security Team