CLEANSTART-2026-ZS57953 authenticated attacker could exceed the session flow control incoming window potentially leading to denial of service

CVE-2026-66275 affects multiple packages. An authenticated attacker could exceed the session flow control incoming window potentially leading to denial of service. See references for individual vulnerability details...

DEBIAN-CVE-2026-85534

A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGSINITIALWINDOWSIZE while that buffered read is still in progres...

CVE-2026-85534

A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGSINITIALWINDOWSIZE while that buffered read is still in progres...

CVE-2026-85534 Libsoup: libsoup: http/2 client crash in on_data_source_read_callback when settings initial_window_size shrinks during deferred body read

A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGSINITIALWINDOWSIZE while that buffered read is still in progres...

CVE-2026-85534

A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGSINITIALWINDOWSIZE while that buffered read is still in progres...

CVE-2026-85534: Reachable Assertion

A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGSINITIALWINDOWSIZE while that buffered read is still in progres...

httpd: httpd: HTTP/2 Remote Denial of Service via compression bomb and Slowloris-style attack

A flaw was found in HTTP/2, affecting various web servers. A remote attacker can exploit this vulnerability by combining an HPACK compression bomb with a zero-byte flow-control window. This technique allows a small amount of data to expand into large memory allocations on the server, which are th...

HTTP/2: request for large response leads to denial of service

A vulnerability was found in HTTP/2. An attacker can open a HTTP/2 window so the peer can send without constraint. The TCP window remains closed so the peer cannot write the bytes on the wire. The attacker then sends a stream of requests for a large response object. Depending on how the server's...

www/varnish7 -- Denial of Service

The Varnish Development Team reports: A denial of service attack can be performed on Varnish Cacher servers that have the HTTP/2 protocol turned on. An attacker can let the servers HTTP/2 connection control flow window run out of credits indefinitely and prevent progress in the processing of...