Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service. The attacker creates multiple request streams and continually shuffles the priority of the streams in a way that causes substantial churn to the priority tree. This can consume excess CPU.

Multiple TCP implementations with Protection Against Wrapped Sequence Numbers (PAWS) with the timestamps option enabled allow remote attackers to cause a denial of service (connection loss) via a spoofed packet with a large timer value, which causes the host to discard later packets because they appear to be too old.

Nginx NJS v0.7.10 was discovered to contain an illegal memcpy via the function njs_vmcode_return at src/njs_vmcode.c.

The Diffie-Hellman Key Agreement Protocol allows remote attackers (from the client side) to send arbitrary numbers that are actually not public keys, and trigger expensive server-side DHE modular-exponentiation calculations, aka a D(HE)at or D(HE)ater attack. The client needs very little CPU resources and network bandwidth. The attack may be more disruptive in cases where a client can require a server to select its largest supported key size. The basic attack scenario is that the client must claim that it can only communicate with DHE, and the server must be configured to allow DHE.

Some HTTP/2 implementations are vulnerable to a reset flood, potentially leading to a denial of service. The attacker opens a number of streams and sends an invalid request over each stream that should solicit a stream of RST_STREAM frames from the peer. Depending on how the peer queues the RST_STREAM frames, this can consume excess memory, CPU, or both.

Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service. The attacker sends a stream of SETTINGS frames to the peer. Since the RFC requires that the peer reply with one acknowledgement per SETTINGS frame, an empty SETTINGS frame is almost equivalent in behavior to a ping. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both.

In F5 BIG-IP 12.1.0 through 12.1.2, specific websocket traffic patterns may cause a disruption of service for virtual servers configured to use the websocket profile.

The RESOLV::lookup iRule command in F5 BIG-IP LTM, APM, ASM, and Link Controller 10.2.1 through 10.2.4, 11.2.1, 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1, and 12.0.0 before HF3; BIG-IP AAM, AFM, and PEM 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1, and 12.0.0 before HF3; BIG-IP Analytics 11.2.1, 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1, and 12.0.0 before HF3; BIG-IP DNS 12.0.0 before HF3; BIG-IP Edge Gateway, WebAccelerator, and WOM 10.2.1 through 10.2.4 and 11.2.1; BIG-IP GTM 10.2.1 through 10.2.4, 11.2.1, 11.4.x, 11.5.x before 11.5.4 HF2, and 11.6.x before 11.6.1; and BIG-IP PSM 10.2.1 through 10.2.4 and 11.4.0 through 11.4.1 allows remote DNS servers to cause a denial of service (CPU consumption or Traffic Management Microkernel crash) via a crafted PTR response.

When BIG-IP 14.0.0-14.1.0.1, 13.0.0-13.1.1.4, 12.1.0-12.1.4, 11.6.1-11.6.3.4, and 11.5.2-11.5.8 are processing certain rare data sequences occurring in PPTP VPN traffic, the BIG-IP system may execute incorrect logic. The TMM may restart and produce a core file as a result of this condition. The BIG-IP system provisioned with the CGNAT module and configured with a virtual server using a PPTP profile is exposed to this vulnerability.

On version 14.0.0-14.1.0.1, BIG-IP virtual servers with TLSv1.3 enabled may experience a denial of service due to undisclosed incoming messages.

On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, 12.1.0-12.1.5, and 11.5.1-11.6.5.1, undisclosed traffic flow may cause TMM to restart under some circumstances.

On BIG-IP 14.0.0-14.1.0.1, 13.0.0-13.1.1.4, 12.1.0-12.1.4, 11.6.1-11.6.3.4, and 11.5.2-11.5.8, DNS query TCP connections that are aborted before receiving a response from a DNS cache may cause TMM to restart.

On BIG-IP versions 15.0.0-15.0.1.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, the Traffic Management Microkernel (TMM) might stop responding after the total number of diameter connections and pending messages on a single virtual server has reached 32K.

On BIG-IP 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, 13.0.0-13.1.1.4, and 12.1.0-12.1.4, undisclosed traffic sent to BIG-IP iSession virtual server may cause the Traffic Management Microkernel (TMM) to restart, resulting in a Denial-of-Service (DoS).

On versions 15.0.0-15.0.1.1, 14.1.0-14.1.2.2, 14.0.0-14.0.1, 13.1.0-13.1.3.2, 12.1.0-12.1.5, and 11.5.2-11.6.5.1, BIG-IP virtual servers with Loose Initiation enabled on a FastL4 profile may be subject to excessive flow usage under undisclosed conditions.

On versions 15.0.0-15.0.1 and 14.0.0-14.1.2, when the BIG-IP is configured in HTTP/2 Full Proxy mode, specifically crafted requests may cause a disruption of service provided by the Traffic Management Microkernel (TMM).

On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.2, 14.0.0-14.0.1, and 13.1.0-13.1.3.1, under certain conditions tmm may leak memory when processing packet fragments, leading to resource starvation.

In BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, 12.1.0-12.1.3.6, 11.6.1-11.6.3.2, or 11.5.1-11.5.8, when processing fragmented ClientHello messages in a DTLS session TMM may corrupt memory eventually leading to a crash. Only systems offering DTLS connections via APM are impacted.

On BIG-IP 14.1.0-14.1.2, 14.0.0-14.0.1, and 13.1.0-13.1.1, undisclosed HTTP requests may consume excessive amounts of systems resources which may lead to a denial of service.

On BIG-IP versions 15.0.0-15.0.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.2, 12.1.0-12.1.5, and 11.5.2-11.6.5, while processing traffic through a standard virtual server that targets a FastL4 virtual server (VIP on VIP), hardware appliances may stop responding.

On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, and 13.1.0-13.1.1.4, the TMM process may produce a core file when an upstream server or cache sends the BIG-IP an invalid age header value.

On BIG-IP PEM 14.1.0-14.1.0.5 and 14.0.0-14.0.0.4, under certain conditions, the TMM process may terminate and restart while processing BIG-IP PEM traffic with the OpenVPN classifier.

On versions 17.0.x before 17.0.0.2, 16.1.x before 16.1.3.3, 15.1.x before 15.1.8, 14.1.x before 14.1.5.3, and all versions of 13.1.x, when a BIG-IP AFM NAT policy with a destination NAT rule is configured on a FastL4 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.

On version 16.x before 16.1.0, 15.1.x before 15.1.3.1, 14.1.x before 14.1.4.3, and all versions of 13.1.x, 12.1.x and 11.6.x, when BIG-IP APM performs Online Certificate Status Protocol (OCSP) verification of a certificate that contains Authority Information Access (AIA), undisclosed requests may cause an increase in memory use. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

On BIG-IP versions 17.0.x before 17.0.0.2 and 16.1.x before 16.1.3.3, when a HTTP profile with the non-default Enforcement options of Enforce HTTP Compliance and Unknown Methods: Reject are configured on a 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.

When a BIG-IP APM virtual server is configured to use a PingAccess profile, undisclosed requests can cause TMM to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

When an HTTP profile with the Enforce RFC Compliance option is configured on a 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.

On versions 15.0.0-15.0.1.1, 14.0.0-14.1.2.2, 13.1.0-13.1.3.1, 12.1.0-12.1.5, and 11.5.2-11.6.5.1, the BIG-IP ASM system may consume excessive resources when processing certain types of HTTP responses from the origin web server. This vulnerability is only known to affect resource-constrained systems in which the security policy is configured with response-side features, such as Data Guard or response-side learning.

On BIG-IP 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, 13.0.0-13.1.1.4, and 12.1.0-12.1.4, an undisclosed traffic pattern sent to a BIG-IP UDP virtual server may lead to a denial-of-service (DoS).

On BIG-IP 14.0.0-14.1.0.1, 13.0.0-13.1.1.4, and 12.1.0-12.1.4, the Traffic Management Microkernel (TMM) may restart when a virtual server has an HTTP/2 profile with Application Layer Protocol Negotiation (ALPN) enabled and it processes traffic where the ALPN extension size is zero.

When a BIG-IP PEM system is licensed with URL categorization, and the URL categorization policy or an iRule with the urlcat command is enabled on a 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.

In BIG-IP 11.5.1-11.5.8, 11.6.1-11.6.3, 12.1.0-12.1.3, and 13.0.0-13.0.1, malformed TCP packets sent to a self IP address or a FastL4 virtual server may cause an interruption of service. The control plane is not exposed to this issue. This issue impacts the data plane virtual servers and self IPs.

On BIG-IP 11.5.1-11.5.8, 11.6.1-11.6.3, and 12.0.x, an undisclosed sequence of packets received by an SSL virtual server and processed by an associated Client SSL or Server SSL profile may cause a denial of service.

On BIG-IP AFM 15.0.0-15.0.1, 14.0.0-14.1.2, and 13.1.0-13.1.3.1, when bad-actor detection is configured on a wildcard virtual server on platforms with hardware-based sPVA, the performance of the BIG-IP AFM system is degraded.

On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, 13.1.0-13.1.1.5, 12.1.0-12.1.4.1, and 11.5.1-11.6.5, under certain conditions, TMM may consume excessive resources when processing traffic for a Virtual Server with the FIX (Financial Information eXchange) profile applied.

On F5 SSL Orchestrator 15.0.0-15.0.1 and 14.0.0-14.1.2, TMM may crash when processing SSLO data in a service-chaining configuration.

When the BIG-IP APM 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, 12.1.0-12.1.4.1, or 11.5.1-11.6.5 system processes certain requests, the APD/APMD daemon may consume excessive resources.

Under some circumstances on BIG-IP 12.0.0-12.1.0, 11.6.0-11.6.1, or 11.4.0-11.5.4 HF1, the Traffic Management Microkernel (TMM) may not properly clean-up pool member network connections when using SPDY or HTTP/2 virtual server profiles.

The default configuration of the IPsec IKE peer listener in F5 BIG-IP LTM, Analytics, APM, ASM, and Link Controller 11.2.1 before HF16, 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1, and 12.x before 12.0.0 HF2; BIG-IP AAM, AFM, and PEM 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1, and 12.x before 12.0.0 HF2; BIG-IP DNS 12.x before 12.0.0 HF2; BIG-IP Edge Gateway, WebAccelerator, and WOM 11.2.1 before HF16; BIG-IP GTM 11.2.1 before HF16, 11.4.x, 11.5.x before 11.5.4 HF2, and 11.6.x before 11.6.1; and BIG-IP PSM 11.4.0 through 11.4.1 improperly enables the anonymous IPsec IKE peer configuration object, which allows remote attackers to establish an IKE Phase 1 negotiation and possibly conduct brute-force attacks against Phase 2 negotiations via unspecified vectors.

Virtual servers in F5 BIG-IP 11.5.4, when SSL profiles are enabled, allow remote attackers to cause a denial of service (resource consumption and Traffic Management Microkernel restart) via an SSL alert during the handshake.

Virtual servers in F5 BIG-IP systems 11.2.1 HF11 through HF15, 11.4.1 HF4 through HF10, 11.5.3 through 11.5.4, 11.6.0 HF5 through HF7, and 12.0.0, when configured with a TCP profile, allow remote attackers to cause a denial of service (Traffic Management Microkernel restart) via crafted network traffic.

os/unix/ngx_files.c in nginx before 1.10.1 and 1.11.x before 1.11.1 allows remote attackers to cause a denial of service (NULL pointer dereference and worker process crash) via a crafted request, involving writing a client request body to a temporary file.

Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.

On versions 15.0.x before 15.1.0 and 14.1.x before 14.1.4, the BIG-IP system provides an option to connect HTTP/2 clients to HTTP/1.x servers. When a client is slow to accept responses and it closes a connection prematurely, the BIG-IP system may indefinitely retain some streams unclosed. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.

Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit f070ef2ac66716357066b683fb0baf55f8191a2e.

On version 16.0.x before 16.0.1.2, 15.1.x before 15.1.3.1, 14.1.x before 14.1.4.2, and 13.1.x before 13.1.4, when JSON content profiles are configured for URLs as part of an F5 Advanced Web Application Firewall (WAF)/BIG-IP ASM security policy and applied to a virtual server, undisclosed requests may cause the BIG-IP ASM bd process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Nginx NJS v0.7.2 to v0.7.4 was discovered to contain a segmentation violation via njs_scope_valid_value at njs_scope.h. NOTE: the vendor disputes the significance of this report because NJS does not operate on untrusted input.

Interaction between the sks-keyserver code through 1.2.0 of the SKS keyserver network, and GnuPG through 2.2.16, makes it risky to have a GnuPG keyserver configuration line referring to a host on the SKS keyserver network. Retrieving data from this network may cause a persistent denial of service, because of a Certificate Spamming Attack.

Nginx NJS v0.7.4 was discovered to contain a segmentation violation in njs_promise_reaction_job. NOTE: the vendor disputes the significance of this report because NJS does not operate on untrusted input.

The resolver in nginx before 1.8.1 and 1.9.x before 1.9.10 does not properly limit CNAME resolution, which allows remote attackers to cause a denial of service (worker process resource consumption) via vectors related to arbitrary name resolution.