Design/Logic Flaw

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...

Code injection

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...

Design/Logic Flaw

Some HTTP/2 implementations are vulnerable to ping floods, potentially leading to a denial of service. The attacker sends continual pings to an HTTP/2 peer, causing the peer to build an internal queue of responses. Depending on how efficiently this data is queued, this can consume excess CPU,...

Design/Logic Flaw

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 RSTSTREAM frames from the peer. Depending on how the peer queues the...

Design/Logic Flaw

Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write many of the byt...

CVE-2019-9511

CVE-2019-9511 is an HTTP/2 denial-of-service issue observed in multiple products where an attacker manipulates HTTP/2 window size and stream prioritization to force queuing of data in 1-byte chunks, potentially exhausting CPU/memory. Connected advisories confirm affected components include nginx ...

CVE-2019-9513

CVE-2019-9513 (and related HTTP/2 CVEs) affect nginx and nghttp2. The issues enable denial of service via HTTP/2 resource loops and priority/window manipulation, causing high CPU/memory usage. nginx 1.16.x and nghttp2 are specifically named in advisories; remediation is upgrading to fixed package...

Excessive CPU usage in HTTP/2 with small window updates

Excessive CPU usage in HTTP/2 with small window updates Severity: medium CVE-2019-9511 Not vulnerable: 1.17.3+, 1.16.1+ Vulnerable: 1.9.5-1.17.2...

Excessive CPU usage in HTTP/2 with priority changes

Excessive CPU usage in HTTP/2 with priority changes Severity: low CVE-2019-9513 Not vulnerable: 1.17.3+, 1.16.1+ Vulnerable: 1.9.5-1.17.2...

CVE-2019-9513 Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service

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...

CVE-2019-9511 Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service

Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service. The attacker requests a large amount of data from a specified resource over multiple streams. They manipulate window size and stream priority ...

CVE-2019-9511

Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service. The attacker requests a large amount of data from a specified resource over multiple streams. They manipulate window size and stream priority ...

CVE-2019-9513

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...

CVE-2019-9513

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...

CVE-2019-9516 Some HTTP/2 implementations are vulnerable to a header leak, potentially leading to a denial of service

Some HTTP/2 implementations are vulnerable to a header leak, potentially leading to a denial of service. The attacker sends a stream of headers with a 0-length header name and 0-length header value, optionally Huffman encoded into 1-byte or greater headers. Some implementations allocate memory fo...

CVE-2019-9518 Some HTTP/2 implementations are vulnerable to a flood of empty frames, potentially leading to a denial of service

Some HTTP/2 implementations are vulnerable to a flood of empty frames, potentially leading to a denial of service. The attacker sends a stream of frames with an empty payload and without the end-of-stream flag. These frames can be DATA, HEADERS, CONTINUATION and/or PUSHPROMISE. The peer spends ti...

CVE-2019-9517 Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service

Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write many of the byt...

CVE-2019-9516

CVE-2019-9516 is an HTTP/2 header leak vulnerability affecting nginx and several Linux distributions. The issue occurs when an attacker sends streams with 0-length header names and values (optionally Huffman encoded), causing nginx to allocate memory for headers that may be kept until the session...

CVE-2019-9518

Some HTTP/2 implementations are vulnerable to a flood of empty frames, potentially leading to a denial of service. The attacker sends a stream of frames with an empty payload and without the end-of-stream flag. These frames can be DATA, HEADERS, CONTINUATION and/or PUSHPROMISE. The peer spends ti...

CVE-2019-9517

Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write many of the byt...