Medium severity · published Oct 26, 2026
CVE-2026-116541
netty-tcnative before 2.0.84.Final Denial of Service via BIO Write Overcount
New
5.9
CVSS
0.5%
EPSS
No
On KEV
Description
Netty netty-tcnative before 2.0.84.Final contains a denial of service vulnerability in the tcn_write_to_bytebuffer BIO write callback that overreports bytes consumed. Remote TLS 1.3 peers can provoke queued post-handshake records like NewSessionTicket or KeyUpdate to truncate flights, fail connections, or abort the JVM process.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
netty-tcnative · netty
before 2.0.84.Final · source: vendor
NE
netty-tcnative-boringssl-static · netty
before 2.0.84.Final · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-116541
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-116541
github.com
https://github.com/netty/netty-tcnative
github.com
https://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/ssl.c#L240
github.com
https://github.com/netty/netty-tcnative/commit/e31df4a5885b35085fdfa3e2dca7c1f705d4745b
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/security/advisories/GHSA-9xr3-jwv4-r489
www.vulncheck.com
https://www.vulncheck.com/advisories/netty-tcnative-before-2.0.84-final-denial-of-service-via-bio-write-overcount
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