Norman Maurer

37 exploits Active since Feb 2021
CVE-2021-43797 WRITEUP MEDIUM WRITEUP
Netty <4.1.71.Final - HTTP Request Smuggling
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. Netty prior to version 4.1.71.Final skips control chars when they are present at the beginning / end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to "sanitize" header names before it forward these to another remote system when used as proxy. This remote system can't see the invalid usage anymore, and therefore does not do the validation itself. Users should upgrade to version 4.1.71.Final.
CVSS 6.5
CVE-2022-24823 WRITEUP MEDIUM WRITEUP
Netty < 4.1.77 - Local Information Disclosure via Temporary File Permissions
Netty is an open-source, asynchronous event-driven network application framework. The package `io.netty:netty-codec-http` prior to version 4.1.77.Final contains an insufficient fix for CVE-2021-21290. When Netty's multipart decoders are used local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk is enabled. This only impacts applications running on Java version 6 and lower. Additionally, this vulnerability impacts code running on Unix-like systems, and very old versions of Mac OSX and Windows as they all share the system temporary directory between all users. Version 4.1.77.Final contains a patch for this vulnerability. As a workaround, specify one's own `java.io.tmpdir` when starting the JVM or use DefaultHttpDataFactory.setBaseDir(...) to set the directory to something that is only readable by the current user.
CVSS 5.5
CVE-2023-34462 WRITEUP MEDIUM WRITEUP
Netty < 4.1.94 - Denial of Service via SniHandler Heap Allocation
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. The `SniHandler` can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle timeout, it can be used to make a TCP server using the `SniHandler` to allocate 16MB of heap. The `SniHandler` class is a handler that waits for the TLS handshake to configure a `SslHandler` according to the indicated server name by the `ClientHello` record. For this matter it allocates a `ByteBuf` using the value defined in the `ClientHello` record. Normally the value of the packet should be smaller than the handshake packet but there are not checks done here and the way the code is written, it is possible to craft a packet that makes the `SslClientHelloHandler`. This vulnerability has been fixed in version 4.1.94.Final.
CVSS 6.5
CVE-2024-29025 WRITEUP MEDIUM WRITEUP
Netty < 4.1.108 - Denial of Service via HttpPostRequestDecoder
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. The `HttpPostRequestDecoder` can be tricked to accumulate data. While the decoder can store items on the disk if configured so, there are no limits to the number of fields the form can have, an attacher can send a chunked post consisting of many small fields that will be accumulated in the `bodyListHttpData` list. The decoder cumulates bytes in the `undecodedChunk` buffer until it can decode a field, this field can cumulate data without limits. This vulnerability is fixed in 4.1.108.Final.
CVSS 5.3
CVE-2024-40642 WRITEUP HIGH WRITEUP
netty-incubator-codec-ohttp < 0.0.13 - HTTP Request Smuggling and Injection via BinaryHttpParser
The netty incubator codec.bhttp is a java language binary http parser. In affected versions the `BinaryHttpParser` class does not properly validate input values thus giving attackers almost complete control over the HTTP requests constructed from the parsed output. Attackers can abuse several issues individually to perform various injection attacks including HTTP request smuggling, desync attacks, HTTP header injections, request queue poisoning, caching attacks and Server Side Request Forgery (SSRF). Attacker could also combine several issues to create well-formed messages for other text-based protocols which may result in attacks beyond the HTTP protocol. The BinaryHttpParser class implements the readRequestHead method which performs most of the relevant parsing of the received request. The data structure prefixes values with a variable length integer value. The parsing code below first gets the lengths of the values from the prefixed variable length integer. After it has all of the lengths and calculates all of the indices, the parser casts the applicable slices of the ByteBuf to String. Finally, it passes these values into a new `DefaultBinaryHttpRequest` object where no further parsing or validation occurs. Method is partially validated while other values are not validated at all. Software that relies on netty to apply input validation for binary HTTP data may be vulnerable to various injection and protocol based attacks. This issue has been addressed in version 0.0.13.Final. Users are advised to upgrade. There are no known workarounds for this vulnerability.
CVSS 8.1
CVE-2024-47535 WRITEUP MEDIUM WRITEUP
Netty < 4.1.115 - Denial of Service via Environment File Read
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. An unsafe reading of environment file could potentially cause a denial of service in Netty. When loaded on an Windows application, Netty attempts to load a file that does not exist. If an attacker creates such a large file, the Netty application crashes. This vulnerability is fixed in 4.1.115.
CVSS 5.5
CVE-2025-24970 WRITEUP HIGH WRITEUP
Netty <4.1.118.Final - Buffer Overflow
Netty, an asynchronous, event-driven network application framework, has a vulnerability starting in version 4.1.91.Final and prior to version 4.1.118.Final. When a special crafted packet is received via SslHandler it doesn't correctly handle validation of such a packet in all cases which can lead to a native crash. Version 4.1.118.Final contains a patch. As workaround its possible to either disable the usage of the native SSLEngine or change the code manually.
CVSS 7.5
CVE-2025-25193 WRITEUP MEDIUM WRITEUP
Netty <= 4.1.118.Final - Denial of Service via Environment File Read
Netty, an asynchronous, event-driven network application framework, has a vulnerability in versions up to and including 4.1.118.Final. An unsafe reading of environment file could potentially cause a denial of service in Netty. When loaded on an Windows application, Netty attempts to load a file that does not exist. If an attacker creates such a large file, the Netty application crash. A similar issue was previously reported as CVE-2024-47535. This issue was fixed, but the fix was incomplete in that null-bytes were not counted against the input limit. Commit d1fbda62d3a47835d3fb35db8bd42ecc205a5386 contains an updated fix.
CVSS 5.5
CVE-2025-29908 WRITEUP MEDIUM WRITEUP
Netty QUIC codec <0.0.71. Final - Hash DoS
Netty QUIC codec is a QUIC codec for netty which makes use of quiche. An issue was discovered in the codec. A hash collision vulnerability (in the hash map used to manage connections) allows remote attackers to cause a considerable CPU load on the server (a Hash DoS attack) by initiating connections with colliding Source Connection IDs (SCIDs). This vulnerability is fixed in 0.0.71.Final.
CVSS 5.3
CVE-2025-58056 WRITEUP HIGH WRITEUP
Netty < 4.1.125 - HTTP Request Smuggling via Inconsistent Chunked Transfer Encoding
Netty is an asynchronous event-driven network application framework for development of maintainable high performance protocol servers and clients. In versions 4.1.124.Final, and 4.2.0.Alpha3 through 4.2.4.Final, Netty incorrectly accepts standalone newline characters (LF) as a chunk-size line terminator, regardless of a preceding carriage return (CR), instead of requiring CRLF per HTTP/1.1 standards. When combined with reverse proxies that parse LF differently (treating it as part of the chunk extension), attackers can craft requests that the proxy sees as one request but Netty processes as two, enabling request smuggling attacks. This is fixed in versions 4.1.125.Final and 4.2.5.Final.
CVSS 7.5
CVE-2025-58057 WRITEUP HIGH WRITEUP
Netty < 4.1.125 - Denial of Service via BrotliDecoder Decompression
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In netty-codec-compression versions 4.1.124.Final and below, and netty-codec versions 4.2.4.Final and below, when supplied with specially crafted input, BrotliDecoder and certain other decompression decoders will allocate a large number of reachable byte buffers, which can lead to denial of service. BrotliDecoder.decompress has no limit in how often it calls pull, decompressing data 64K bytes at a time. The buffers are saved in the output list, and remain reachable until OOM is hit. This is fixed in versions 4.1.125.Final of netty-codec and 4.2.5.Final of netty-codec-compression.
CVSS 7.5
CVE-2025-59419 WRITEUP MEDIUM WRITEUP
Netty < 4.1.128.Final and 4.2.0.Alpha1-4.2.7.Final - SMTP Command Injection via CRLF Sequence
Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.128.Final and 4.2.7.Final, the SMTP codec in Netty contains an SMTP command injection vulnerability due to insufficient input validation for Carriage Return (\r) and Line Feed (\n) characters in user-supplied parameters. The vulnerability exists in io.netty.handler.codec.smtp.DefaultSmtpRequest, where parameters are directly concatenated into the SMTP command string without sanitization. When methods such as SmtpRequests.rcpt(recipient) are called with a malicious string containing CRLF sequences, attackers can inject arbitrary SMTP commands. Because the injected commands are sent from the server's trusted IP address, resulting emails will likely pass SPF and DKIM authentication checks, making them appear legitimate. This allows remote attackers who can control SMTP command parameters (such as email recipients) to forge arbitrary emails from the trusted server, potentially impersonating executives and forging high-stakes corporate communications. This issue has been patched in versions 4.1.129.Final and 4.2.8.Final. No known workarounds exist.