Where
-Infinity
0
Severity
9.1
AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote attacker to perform request smuggling. Request smuggling allows an attacker to bypass security mechanisms, access restricted information, or manipulate web caches, potentially leading to unauthorized actions or data exposure.

1 / 2
Source: MITRE
First published (updated )
Severity
9.1
AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request smuggling attacks, potentially bypassing security controls and accessing unauthorized resources.

1 / 2
Source: MITRE
First published (updated )
Severity
9.1
AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending \r\r\r as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests.

1 / 2
Source: MITRE
First published (updated )
Severity
9.6
Input Validation, SSRF
AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests. As a result, requests containing malformed or malicious Host headers are processed without rejection, enabling attackers to poison caches, perform internal network scans, or hijack user sessions.

1 / 4
Source: GitHub
First published (updated )
Severity
7.5
EPSS
0.61%
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters. This issue, referred to as the "MadeYouReset" attack, allows malicious clients to induce excessive server workload by repeatedly causing server-side stream aborts. While not a protocol bug, this highlights a common implementation weakness that can be exploited to cause a denial of service (DoS).

1 / 2
Source: MITRE
First published (updated )
Severity
5.3
Path Traversal
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

A path traversal vulnerability was found in Undertow. This issue may allow a remote attacker to append a specially-crafted sequence to an HTTP request for an application deployed to JBoss EAP, which may permit access to privileged or restricted files and directories.

1 / 2
Source: GitHub
First published (updated )
Severity
7.5
EPSS
0.13%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in Undertow. When an AJP request is sent that exceeds the max-header-size attribute in ajp-listener, JBoss EAP is marked in an error state by modcluster in httpd, causing JBoss EAP to close the TCP connection without returning an AJP response. This happens because modproxycluster marks the JBoss EAP instance as an error worker when the TCP connection is closed from the backend after sending the AJP request without receiving an AJP response, and stops forwarding. This issue could allow a malicious user could to repeatedly send requests that exceed the max-header-size, causing a Denial of Service (DoS).

1 / 2
Source: NVD
First published (updated )
Severity
7.5
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in undertow. Servlets annotated with @MultipartConfig may cause an OutOfMemoryError due to large multipart content. This may allow unauthorized users to cause remote Denial of Service (DoS) attack. If the server uses fileSizeThreshold to limit the file size, it's possible to bypass the limit by setting the file name in the request to null.

1 / 2
Source: GitHub
First published (updated )
Severity
7.5
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in undertow. This issue makes achieving a denial of service possible due to an unexpected handshake status updated in SslConduit, where the loop never terminates.

1 / 3
First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in Undertow. AJP requests to the server may allow an attacker to send a malicious request and trigger server errors, resulting in a denial of service.

1 / 3
First published (updated )
Severity
7.5
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in Undertow where a potential security issue in flow control handling by browser over HTTP/2 may potentially cause overhead or DOS in the server. The highest impact of this vulnerability is availability.

1 / 4
Source: Red Hat
First published (updated )
Severity
4.8
XSS
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

A flaw was found in Undertow. A regression in the fix for CVE-2020-10687 was found. HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a web-cache, perform an XSS attack, or obtain sensitive information from request other than their own. The highest threat from this vulnerability is to data confidentiality and integrity.

1 / 2
First published (updated )
Severity
6.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

A flaw was found in Undertow in versions before 2.1.1.Final, regarding the processing of invalid HTTP requests with large chunk sizes. This flaw allows an attacker to take advantage of HTTP request smuggling.

1 / 3
First published (updated )
Severity
9.8
AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L

A file inclusion vulnerability was found in the AJP connector enabled with a default AJP configuration port of 8009 in Undertow version 2.0.29.Final and before and was fixed in 2.0.30.Final. A remote, unauthenticated attacker could exploit this vulnerability to read web application files from a vulnerable server. In instances where the vulnerable server allows file uploads, an attacker could upload malicious JavaServer Pages (JSP) code within a variety of file types and trigger this vulnerability to gain remote code execution.

1 / 3

Remedy

Please refer to the Red Hat knowledgebase article: https://access.redhat.com/solutions/4851251
First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was discovered in Undertow in versions before Undertow 2.1.1.Final where certain requests to the "Expect: 100-continue" header may cause an out of memory error. This flaw may potentially lead to a denial of service.

1 / 3

Remedy

There is currently no known mitigation for this security flaw.
First published (updated )
Severity
4.8
XSS
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

A flaw was discovered in all versions of Undertow before Undertow 2.2.0.Final, where HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a web-cache, perform an XSS attack, or obtain sensitive information from request other than their own.

1 / 3
First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in Undertow as shipped in Jboss EAP before version 7.2.4. A memory leak in HttpOpenListener due to holding remote connections indefinitely may lead to denial of service.

References:

https://issues.redhat.com/browse/JBEAP-16695

1 / 2
Source: Red Hat
First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A vulnerability was found in the Undertow HTTP server in versions before 2.0.28.SP1 when listening on HTTPS. An attacker can target the HTTPS port to carry out a Denial Of Service (DOS) to make the service unavailable on SSL.

1 / 2

Remedy

Enable HTTP2 (enable-http2="true") in the undertow's HTTPS settings.
First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

A flaw was found in the Undertow DEBUG log for io.undertow.request.security. If enabled, an attacker could abuse this flaw to obtain the user’s credentials from the log files.

1 / 3

Remedy

Use Elytron instead of legacy Security subsystem.
First published (updated )
Severity
7.5
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

An information leak issue was found in undertow where web apps may have their directory structures predicted through requests without trailing slashes via the api.

1 / 2
Source: Red Hat
First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

A vulnerability was found in Undertow web server before 2.0.21. An information exposure of plain text credentials through log files because Connectors.executeRootHandler:402 logs the HttpServerExchange object at ERROR level using UndertowLogger.REQUESTLOGGER.undertowRequestFailed(t, exchange)

1 / 2
First published (updated )
Severity
8.1
Input Validation, Infoleak
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

A flaw was found in all undertow-2.x.x SP1 versions prior to undertow-2.0.30.SP1, all undertow-1.x.x and undertow-2.x.x versions prior to undertow-2.1.0.Final, where the Servlet container causes servletPath to normalize incorrectly by truncating the path after semicolon which may lead to an application mapping resulting in the security bypass.

1 / 3

Remedy

The issue can be mitigated by configuring UrlPathHelper to ignore the servletPath via setting "alwaysUseFullPath".
First published (updated )
Severity
5.3
Infoleak
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

An information leak vulnerability was found in Undertow. If all headers are not written out in the first write() call then the code that handles flushing the buffer will always write out the full contents of the writevBuffer buffer, which may contain data from previous requests.

1 / 2
First published (updated )
Severity
6.5
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

It was found that URLResource.getLastModified() in Undertow closes the file descriptors only when they are finalized which can cause file descriptors to exhaust. This leads to a file handler leak.

1 / 2
Source: MITRE
First published (updated )
Severity
6.1
CRLF Injection
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

A flaw was reported in WildFly 12.0.0.CR1 web server is vulnerable to the injection of arbitrary HTTP Header due to insufficient sanitisation and validation of user UTF-8 encoded input before it is used as part of an HTTP header value.

Although there is a protection against CRLF injection by detecting the presence of a NewLine character (0x0a), it can be bypassed using characters encoded in UTF-8 as the page will try to convert them back to the original Unicode form and extract the last byte.

1 / 2
Source: Red Hat
First published (updated )
Severity
5.9
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

It was discovered that when using Digest authentication, the server does not ensure that the value of the URI in the authorization header matches the URI in the HTTP request line. This allows the attacker to execute a MITM attack and access the desired content on the server.

1 / 3
First published (updated )
Severity
7.5
AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N

It was discovered that Undertow before 1.4.17, 1.3.31 and 2.0.0 processes http request headers with unusual whitespaces which can cause possible http request smuggling.

1 / 2
First published (updated )
Severity
6.5
XSS
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

In Undertow 2.x before 2.0.0.Alpha2, 1.4.x before 1.4.17.Final, and 1.3.x before 1.3.31.Final, it was found that the fix for CVE-2017-2666 was incomplete and invalid characters are still allowed in the query string and path parameters. This could be exploited, in conjunction with a proxy that also permitted the invalid characters but with a different interpretation, to inject data into the HTTP response. By manipulating the HTTP response the attacker could poison a web-cache, perform an XSS attack, or obtain sensitive information from requests other than their own.

1 / 3
First published (updated )
Severity
6.5
XSS
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

It was discovered in Undertow that the code that parsed the HTTP request line permitted invalid characters. This could be exploited, in conjunction with a proxy that also permitted the invalid characters but with a different interpretation, to inject data into the HTTP response. By manipulating the HTTP response the attacker could poison a web-cache, perform an XSS attack, or obtain sensitive information from requests other than their own.

1 / 3
First published (updated )

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