CVE-2026-45674 Netty Vulnerable to DNS Cache Poisoning via Missing Bailiwick Checks in CNAME Records
Netty fails to validate CNAME record origins, allowing DNS cache poisoning attacks that bypass security controls.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45674?
CVE-2026-45674 is a high-severity vulnerability in Netty Netty, published on 12 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty's DnsResolveContext fails to validate the origin (bailiwick) of CNAME records in DNS responses. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
Which versions are affected by CVE-2026-45674?
4 open source packages ship an affected version, including io.netty:netty-resolver-dns. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
io.netty:netty-resolver-dns Maven | All versions | 4.1.135.Final |
io.netty:netty-resolver-dns Maven | All versions | 4.1.135.Final |
io.netty:netty-resolver-dns Maven | From 4.2.0.Final | 4.2.15.Final |
io.netty:netty-resolver-dns Maven | From 4.2.0.Final | 4.2.15.Final |
Products include Netty Netty.
How do I fix CVE-2026-45674?
Upgrade io.netty:netty-resolver-dns to a fixed version for your release line: 4.1.135.Final or 4.2.15.Final.
Is CVE-2026-45674 being exploited?
There is no known exploitation of CVE-2026-45674 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Netty Netty
- CVE-2026-75595 Netty: SNI Routing Bypass via Fragmented TLS ClientHello Causing Fallback to Default SslContext
- CVE-2026-75596 Netty: Fragmented ClientHello records trigger quadratic pre-handshake reassembly in default SNI parsing
- CVE-2026-59901 Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang
- CVE-2026-55851 Netty codec-haproxy: Signed-Byte Sentinel Collision in HAProxyMessageDecoder Leads to Unbounded Memory Exhaustion
- CVE-2026-56745 Netty SpdyHttpDecoder: ByteBuf Reference Leak on RST_STREAM Leads to Native Memory Exhaustion
Sources
Also known as CLEANSTART-2026-AG72812, CLEANSTART-2026-CD10863, CLEANSTART-2026-JI47500, CLEANSTART-2026-NB58291, DEBIAN-CVE-2026-45674, ECHO-b66e-8a32-1e5f and 81 more.