If an attempt is made to create an item of a type prohibited by `ACL#hasCreatePermission2` or `TopLevelItemDescriptor#isApplicableIn(ItemGroup)` through the Jenkins CLI or the REST API and either of these checks fail, Jenkins 2.478 and earlier, LTS 2.462.2 and earlier creates the item in memory, only deleting it from disk, allowing attackers with Item/Configure permission to save the item to persist it, effectively bypassing the item creation restriction.

Jenkins 2.478 and earlier, LTS 2.462.2 and earlier does not redact multi-line secret values in error messages generated for form submissions involving the `secretTextarea` form field.

Jenkins 2.470 and earlier, LTS 2.452.3 and earlier does not perform a permission check in an HTTP endpoint, allowing attackers with Overall/Read permission to access other users' "My Views".

Jenkins 2.470 and earlier, LTS 2.452.3 and earlier allows agent processes to read arbitrary files from the Jenkins controller file system by using the `ClassLoaderProxy#fetchJar` method in the Remoting library.

Jenkins 2.217 through 2.441 (both inclusive), LTS 2.222.1 through 2.426.2 (both inclusive) does not perform origin validation of requests made through the CLI WebSocket endpoint, resulting in a cross-site WebSocket hijacking (CSWSH) vulnerability, allowing attackers to execute CLI commands on the Jenkins controller.

Jenkins 2.441 and earlier, LTS 2.426.2 and earlier does not disable a feature of its CLI command parser that replaces an '@' character followed by a file path in an argument with the file's contents, allowing unauthenticated attackers to read arbitrary files on the Jenkins controller file system.

Eclipse Jetty provides a web server and servlet container. In versions 11.0.0 through 11.0.15, 10.0.0 through 10.0.15, and 9.0.0 through 9.4.52, an integer overflow in `MetaDataBuilder.checkSize` allows for HTTP/2 HPACK header values to exceed their size limit. `MetaDataBuilder.java` determines if a header name or value exceeds the size limit, and throws an exception if the limit is exceeded. However, when length is very large and huffman is true, the multiplication by 4 in line 295 will overflow, and length will become negative. `(_size+length)` will now be negative, and the check on line 296 will not be triggered. Furthermore, `MetaDataBuilder.checkSize` allows for user-entered HPACK header value sizes to be negative, potentially leading to a very large buffer allocation later on when the user-entered size is multiplied by 2. This means that if a user provides a negative length value (or, more precisely, a length value which, when multiplied by the 4/3 fudge factor, is negative), and this length value is a very large positive number when multiplied by 2, then the user can cause a very large buffer to be allocated on the server. Users of HTTP/2 can be impacted by a remote denial of service attack. The issue has been fixed in versions 11.0.16, 10.0.16, and 9.4.53. There are no known workarounds.

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

In Jenkins 2.423 and earlier, LTS 2.414.1 and earlier, processing file uploads using MultipartFormDataParser creates temporary files in the default system temporary directory with the default permissions for newly created files, potentially allowing attackers with access to the Jenkins controller file system to read and write the files before they are used.

In Jenkins 2.423 and earlier, LTS 2.414.1 and earlier, processing file uploads using the Stapler web framework creates temporary files in the default system temporary directory with the default permissions for newly created files, potentially allowing attackers with access to the Jenkins controller file system to read and write the files before they are used.

Jenkins 2.423 and earlier, LTS 2.414.1 and earlier creates a temporary file in the system temporary directory with the default permissions for newly created files when installing a plugin from a URL, potentially allowing attackers with access to the system temporary directory to replace the file before it is installed in Jenkins, potentially resulting in arbitrary code execution.

Jenkins 2.423 and earlier, LTS 2.414.1 and earlier does not escape the value of the 'caption' constructor parameter of 'ExpandableDetailsNote', resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers able to control this parameter.

Jenkins 2.50 through 2.423 (both inclusive), LTS 2.60.1 through 2.414.1 (both inclusive) does not exclude sensitive build variables (e.g., password parameter values) from the search in the build history widget, allowing attackers with Item/Read permission to obtain values of sensitive variables used in builds by iteratively testing different characters until the correct sequence is discovered.

Jenkins 2.415 and earlier, LTS 2.401.2 and earlier does not sanitize or properly encode URLs in build logs when transforming them into hyperlinks, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers able to control build log contents.