When a BIG-IP is configured with DNS caching (Such as a DNS profile with caching enabled, SSL Orchestrator, Advanced WAF DoS protection), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

HTTP/2 Rapid reset attack The HTTP/2 protocol allows clients to indicate to the server that a previous stream should be canceled by sending a RSTSTREAM frame. The protocol does not require the client and server to coordinate the cancellation in any way, the client may do it unilaterally. The client may also assume that the cancellation will take effect immediately when the server receives the RSTSTREAM frame, before any other data from that TCP connection is processed.

Abuse of this feature is called a Rapid Reset attack because it relies on the ability for an endpoint to send a RSTSTREAM frame immediately after sending a request frame, which makes the other endpoint start working and then rapidly resets the request. The request is canceled, but leaves the HTTP/2 connection open.

The HTTP/2 Rapid Reset attack built on this capability is simple: The client opens a large number of streams at once as in the standard HTTP/2 attack, but rather than waiting for a response to each request stream from the server or proxy, the client cancels each request immediately.

The ability to reset streams immediately allows each connection to have an indefinite number of requests in flight. By explicitly canceling the requests, the attacker never exceeds the limit on the number of concurrent open streams. The number of in-flight requests is no longer dependent on the round-trip time (RTT), but only on the available network bandwidth.

In a typical HTTP/2 server implementation, the server will still have to do significant amounts of work for canceled requests, such as allocating new stream data structures, parsing the query and doing header decompression, and mapping the URL to a resource. For reverse proxy implementations, the request may be proxied to the backend server before the RSTSTREAM frame is processed. The client on the other hand paid almost no costs for sending the requests. This creates an exploitable cost asymmetry between the server and the client.

Multiple software artifacts implementing HTTP/2 are affected. This advisory was originally ingested from the swift-nio-http2 repo advisory and their original conent follows.

swift-nio-http2 specific advisory swift-nio-http2 is vulnerable to a denial-of-service vulnerability in which a malicious client can create and then reset a large number of HTTP/2 streams in a short period of time. This causes swift-nio-http2 to commit to a large amount of expensive work which it then throws away, including creating entirely new Channels to serve the traffic. This can easily overwhelm an EventLoop and prevent it from making forward progress.

swift-nio-http2 1.28 contains a remediation for this issue that applies reset counter using a sliding window. This constrains the number of stream resets that may occur in a given window of time. Clients violating this limit will have their connections torn down. This allows clients to continue to cancel streams for legitimate reasons, while constraining malicious actors.

A vulnerability was found in OpenSSL 1.0.2. When an application encounters a fatal protocol error and then calls SSLshutdown() twice, OpenSSL can respond differently to the calling application if a 0 byte record is received with invalid padding compared to if a 0 byte record is received with an invalid MAC. This difference in behaviour can be detected by a remote peer, then this amounts to a padding oracle that could be used to decrypt data. In order for this to be exploitable "non-stitched" ciphersuites must be in use. Also the application must call SSLshutdown() twice even if a protocol error has occurred (applications should not do this but some do anyway). AEAD ciphersuites are not impacted. This issue does not impact OpenSSL 1.1.1 or 1.1.0.

Upstream bug: https://www.openssl.org/news/secadv/20190226.txt

Upstream Patch: https://github.com/openssl/openssl/commit/e9bbefbf0f24c57645e7ad6a5a71ae649d18ac8e

A cross-site scripting vulnerability was discovered in bootstrap. If an attacker could control the data given to tooltip or popover, they could inject HTML or Javascript into the rendered page when tooltip or popover events fired.

A flaw was found in the bash functionality that evaluates specially formatted environment variables passed to it from another environment. An attacker could use this feature to override or bypass restrictions to the environment to execute shell commands before restrictions have been applied. Certain services and applications allow remote unauthenticated attackers to provide environment variables, allowing them to exploit this issue.

Acknowledgements:

Red Hat would like to thank Stephane Chazelas for reporting this issue.

An authenticated attacker's undisclosed requests to BIG-IP iControl REST can lead to an information leak of BIG-IP local user account names.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When running in Appliance mode, a directory traversal vulnerability exists in an undisclosed iControl REST endpoint that may allow an authenticated attacker with administrator role privileges to cross a security boundary and delete files.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When running in Appliance mode, an authenticated remote command injection vulnerability exists in an undisclosed iControl REST endpoint. A successful exploit can allow the attacker to cross a security boundary.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

An authenticated iControl SOAP user may be able to obtain information of other accounts.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in iControl REST and the TMOS Shell (tmsh) where a highly privileged, authenticated attacker with at least the Manager role can create configuration objects that allow running arbitrary commands.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Incorrect permission assignment vulnerabilities exist in iControl REST and TMOS shell (tmsh) undisclosed command which may allow an authenticated attacker to view sensitive information.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in BIG-IP and BIG-IQ systems where a highly privileged, authenticated attacker with at least the Resource Administrator role can create SNMP configuration objects through iControl REST or the TMOS shell (tmsh) resulting in privilege escalation.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

An authenticated attacker with the Resource Administrator or Administrator role can modify configuration objects through iControl SOAP resulting in privilege escalation.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When SSL profiles are configured on a virtual server, undisclosed traffic can cause the virtual server to stop processing new client connections.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When an SSL profile is configured on a virtual server on BIG-IP Virtual Edition (VE) without Intel QuickAssist Technology (QAT) or on BIG-IP hardware platforms with the database variable crypto.hwacceleration set to disabled, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When configured, IP-based access restrictions for httpd do not cover all endpoints, which may allow connections from blocked addresses.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When a SIP profile is configured on a virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When the BIG-IP Configuration utility is configured to use Lightweight Directory Access Protocol (LDAP) authentication, undisclosed traffic can cause the httpd process to exhaust the available file descriptors.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When Bidirectional Forwarding Detection (BFD) is configured in Static and Dynamic routing protocols, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to stop processing BFD packets and cause the configured routing protocol to fail over.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in BIG-IP scripted monitors that may allow an authenticated attacker with the Resource Administrator or Administrator role to execute arbitrary system commands with higher privileges. In appliance mode deployments, a successful exploit can allow the attacker to cross a security boundary.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in BIG-IP and BIG-IQ systems where a highly privileged, authenticated attacker with at least the Certificate Manager role can modify configuration objects that allow running arbitrary commands.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Incorrect permission assignment vulnerabilities exist in BIG-IP and BIG-IQ TMOS Shell (tmsh) network diagnostics commands and in BIG-IP iControl REST. These vulnerabilities may allow an authenticated attacker to view the network status of destination systems.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When a classification profile is configured on a UDP virtual server, undisclosed requests can cause the Traffic Management Microkernel (TMM) to terminate.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Sensitive information disclosure vulnerability exists in the undisclosed iControl REST endpoint and TMOS Shell (tmsh) command which may allow an authenticated attacker with resource administrator role privileges to view sensitive information.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in BIG-IP systems where a highly privileged, authenticated attacker with at least the Resource Administrator role can modify configuration objects resulting in privilege escalation.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in iControl REST where a highly privileged, authenticated attacker with at least the Manager role can create configuration objects that allow running arbitrary commands.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

An improper sanitization vulnerability exists in the BIG-IP QKView utility that allows a low-privileged attacker to read sensitive information from a QKView file.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated

When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the urlcatquery command), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in an undisclosed BIG-IP TMOS Shell (tmsh) command that may allow an authenticated attacker with resource administrator or administrator role to execute arbitrary system commands with higher privileges. In Appliance mode deployments, a successful exploit can allow the attacker to cross a security boundary.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A cross-site request forgery (CSRF) vulnerability exists in the dashboard of the BIG-IP Configuration utility.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.