CVE-2026-116539
Netty netty-tcnative before 2.0.84.Final Heap Buffer Overflow via OpenSSL BIO
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.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| netty-tcnative netty io.netty:netty-tcnative
maven |
≥ 0; < 2.0.84.Final (affected, custom)
Other versions: unaffected |
CNA: VulnCheck |
| netty-tcnative-boringssl-static netty io.netty:netty-tcnative-boringssl-static
maven |
≥ 0; < 2.0.84.Final (affected, custom)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 8.2 high |
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 | CNA: VulnCheck |
| 3.1 / 5.9 medium |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: VulnCheck |
Exploit evidence
- https://github.com/netty/netty-tcnative/security/advisories/GHSA-gf9q-9mg7-g5qh
exploit · ADP: CISA-ADP
References
- https://github.com/netty/netty-tcnative/security/advisories/GHSA-gf9q-9mg7-g5qhCNA: VulnCheck · vendor-advisory
- https://github.com/netty/netty-tcnative/commit/92dd66fd1243d85c05a61288f96367a70260b6b8CNA: VulnCheck · patch
- https://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/ssl.c#L199CNA: VulnCheck · technical-description
- https://github.com/netty/netty-tcnative/releases/tag/netty-tcnative-parent-2.0.84.FinalCNA: VulnCheck · release-notes
- https://github.com/netty/netty-tcnativeCNA: VulnCheck · product
- https://www.vulncheck.com/advisories/netty-netty-tcnative-before-2.0.84-final-heap-buffer-overflow-via-openssl-bioCNA: VulnCheck · third-party-advisory
- https://github.com/netty/netty-tcnative/security/advisories/GHSA-gf9q-9mg7-g5qhADP: CISA-ADP · exploit
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