Denial of service in Netty netty-tcnative via BIO write overcount
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
netty-tcnative and netty-tcnative-boringssl-static before 2.0.84.Final are affected. An incorrect calculation in the tcn_write_to_bytebuffer BIO write callback overreports the bytes consumed (CWE-682). A remote TLS 1.3 peer can trigger queued post-handshake records such as NewSessionTicket or KeyUpdate to truncate flights, fail connections, or abort the JVM process.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade netty-tcnative and netty-tcnative-boringssl-static to 2.0.84.Final. The sources list no fixed version for Red Hat Fuse 7 (no fix planned) or for Red Hat build of Apache Camel for Spring Boot 4 (none available).
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
- Fix · CNA netty-tcnative (netty) Fixed in 2.0.84.Final
- Fix · CNA netty-tcnative-boringssl-static (netty) Fixed in 2.0.84.Final
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
netty-tcnative 2.0.84.Final
4 records Highest priority Priority HIGH 2 HIGH, 2 LOW
Other records, highest priority first
- TI-2026-80456 Heap buffer overflow in Netty netty-tcnative via OpenSSL BIOPriority HIGH 75
- TI-2026-80459 SNI hostname spoofing in Netty netty-tcnative via UTF-8 decodingPriority HIGH 70
- TI-2026-80457 Use-after-free in netty-tcnative session ticket key callbackPriority LOW 36
- Release ·
netty-tcnative-boringssl-static 2.0.84.Final
3 records Highest priority Priority HIGH 2 HIGH, 1 LOW
Other records, highest priority first
- TI-2026-80456 Heap buffer overflow in Netty netty-tcnative via OpenSSL BIOPriority HIGH 75
- TI-2026-80459 SNI hostname spoofing in Netty netty-tcnative via UTF-8 decodingPriority HIGH 70
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Fuse 7 | Affected | No fix planned: Out of support scope |
| Red Hat build of Apache Camel for Spring Boot 4 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-26 Threatist record created from CVE-2026-116541
- 2026-10-26 CISA SSVC decision points changed
- 2026-10-26 Priority changed: MEDIUM → LOW
- 2026-10-27 Alias added: GHSA-rm79-885g-92ch
- 2026-11-04 Affected versions changed · Red Hat
- 2026-11-04 CVSS score added · Red Hat
References
Patch 1
More netty vulnerabilities
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2026-30861 Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization CVSS 3.1CRITICAL 9.8
- TI-2026-30864 Netty: HttpClientCodec response desynchronization CVSS 3.1CRITICAL 9.1
- TI-2026-30859 Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder) CVSS 3.1CRITICAL 9.1
- TI-2026-64821 Netty 4.2.11 through 4.2.17 QUIC Hostname Verification Bypass CVSS 4.0HIGH 8.7
- TI-2026-64818 Netty HTTP/3 QPACK encoder-stream unbounded memory exhaustion DoS CVSS 4.0HIGH 8.7
Sources
- CVE-2026-116541 · CVE Program
- CVE-2026-116541 · NVD
- FIRST EPSS
- GHSA-rm79-885g-92ch · GitHub Advisory Database · CC BY 4.0
- CVE-2026-116541 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences