High Netty-handler CVEs with no public exploit
7 CVEs
Overview 7 matches · 0 protected · 0 exploited · 0 CISA KEV · 0 public PoC · 0 EPSS ≥ 0.5
7matches
0protected0.0%
0exploited0.0%
0CISA KEV0.0%
0public PoC0.0%
0EPSS ≥ 0.50.0%
Protected by Waratek
0
0.0%
Rule in development
0
0.0%
Mitigation candidate
0
0.0%
No exploit published
7
100.0%
blocked by ARMR today
0
0.0%
partly blocked
0
0.0%
not blocked
7
100.0%
not established
0
0.0%
unrecorded
0
0.0%
Exploited
0
0.0%
Working exploit published
0
0.0%
Proof of concept only
0
0.0%
Forecast only
0
0.0%
No public exploit
7
100.0%
split by
peak 4 / year
2017201820192020202120222023202420252026
| CVE | Severity | Published▾ | Status | Exploitation | Description |
|---|---|---|---|---|---|
| CVE-2026-75596 | High | 2026-08-19 | No exploit published | No public exploit | Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, the default io.netty.handler.ssl.SniHandler constructors use the pre-handshake ClientHello aggregation path in handler/src/main/java/io/netty/handler/ssl/SslClientHelloHandler.java at io.netty.handler.ssl.SslClientHelloHandler#decode, where handshakeBuffer.clear() and writeBytes() recopy all previously received body bytes for every additional TLS record. An unauthenticated remote peer can advertise a large ClientHello and deliver its body in thousands of tiny records, causing quadratic CPU work on the event loop before the TLS handshake completes and degrading TLS handling for other clients. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final. |
| CVE-2026-50010 | High | 2026-06-12 | No exploit published | No public exploit | 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, SimpleTrustManagerFactory.engineGetTrustManagers() and related paths wrap any user-supplied plain X509TrustManager in X509TrustManagerWrapper, which extends X509ExtendedTrustManager but implements the 3-arg checkServerTrusted(chain, authType, SSLEngine) by discarding the SSLEngine and calling the 2-arg delegate. Because the object now IS an X509ExtendedTrustManager, neither SunJSSE's internal AbstractTrustManagerWrapper nor Netty's own OpenSslX509TrustManagerWrapper will re-wrap it to add endpoint-identification. Consequently, even though Netty 4.2 sets endpointIdentificationAlgorithm="HTTPS" by default, a client built with `SslContextBuilder.forClient().trustManager(somePlainX509TrustManager)` performs no hostname verification at all. Versions 4.1.135.Final and 4.2.15.Final patch the issue. |
| CVE-2026-45416 | High | 2026-06-12 | No exploit published | No public exploit | 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, SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates `ctx.alloc().buffer(handshakeLength)` (line 161). The guard at line 140 is `handshakeLength > maxClientHelloLength && maxClientHelloLength != 0`, and the commonly-used SniHandler/AbstractSniHandler constructors (SniHandler(Mapping), SniHandler(AsyncMapping), AbstractSniHandler()) pass maxClientHelloLength=0 and handshakeTimeoutMillis=0, so the length guard is disabled and no timeout is scheduled. A 16 MiB request exceeds the default pooled chunk size and becomes a huge/unpooled allocation performed immediately. The buffer is retained in the handler until the channel closes. Versions 4.1.135.Final and 4.2.15.Final patch the issue. |
| CVE-2026-44249 | High | 2026-06-11 | No exploit published | No public exploit | Netty is a network application framework for development of protocol servers and clients. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses can bypass the restrictions. Versions 4.1.135.Final and 4.2.15.Final patch the issue. |
| CVE-2023-4586 | High | 2023-10-04 | No exploit published | No public exploit | A vulnerability was found in the Hot Rod client. This security issue occurs as the Hot Rod client does not enable hostname validation when using TLS, possibly resulting in a man-in-the-middle (MITM) attack. |
| CVE-2020-7238 | High | 2020-01-27 | No exploit published | No public exploit | Netty 4.1.43.Final allows HTTP Request Smuggling because it mishandles Transfer-Encoding whitespace (such as a [space]Transfer-Encoding:chunked line) and a later Content-Length header. This issue exists because of an incomplete fix for CVE-2019-16869. |
| CVE-2016-4970 | High | 2017-04-13 | No exploit published | No public exploit | handler/ssl/OpenSslEngine.java in Netty 4.0.x before 4.0.37.Final and 4.1.x before 4.1.1.Final allows remote attackers to cause a denial of service (infinite loop). |