org.apache.httpcomponents.core5/httpcore5-h2: Apache HttpComponents Core: Denial of Service via oversized HTTP/2 HPACK header blocks

A flaw was found in Apache HttpComponents Core. This vulnerability, located in the HTTP/2 HPACK decoder, allows a remote attacker to cause a denial of service. By sending oversized compressed header blocks, an attacker can exhaust memory resources before the system's configured header list size...

EUVD-2026-50235

Apache Traffic Server updates the HTTP/2 HPACK dynamic table before confirming the header block encoded successfully, so an encode failure leaves the encoder out of sync with the peer decoder and corrupts subsequent header blocks on the connection. This issue affects Apache Traffic Server: from...

CVE-2026-65100

Apache Traffic Server updates the HTTP/2 HPACK dynamic table before confirming the header block encoded successfully, so an encode failure leaves the encoder out of sync with the peer decoder and corrupts subsequent header blocks on the connection. This issue affects Apache Traffic Server: from...

EUVD-2026-50204

Apache Traffic Server mishandles integers while decoding HPACK/XPACK headers, corrupting memory. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the...

CVE-2026-58152

Apache Traffic Server mishandles integers while decoding HPACK/XPACK headers, corrupting memory. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the...

PT-2026-65729

Apache Traffic Server mishandles integers while decoding HPACK/XPACK headers, corrupting memory. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the...

cowlib: Cowlib: Denial of Service due to unbounded HPACK/QPACK prefixed-integer decoding

A flaw was found in cowlib, an HTTP parser. An unauthenticated remote attacker could exploit this vulnerability by sending specially crafted HTTP/2 or HTTP/3 frames containing oversized HPACK or QPACK prefixed integers. This unbounded decoding process leads to excessive memory allocation and...

CVE-2026-59248

A flaw was found in cowlib, an HTTP parser. An unauthenticated remote attacker could exploit this vulnerability by sending specially crafted HTTP/2 or HTTP/3 frames containing oversized HPACK or QPACK prefixed integers. This unbounded decoding process leads to excessive memory allocation and...

EUVD-2026-49739

Allocation of resources without limits vulnerability in ninenines cowlib allows an unauthenticated remote HTTP/2 or HTTP/3 peer to exhaust memory on the vulnerable server or client and cause a denial of service. The HPACK and QPACK prefixed-integer decoder cowhpackcommon:decbigint/3 in...

CVE-2026-59248

Allocation of resources without limits vulnerability in ninenines cowlib allows an unauthenticated remote HTTP/2 or HTTP/3 peer to exhaust memory on the vulnerable server or client and cause a denial of service. The HPACK and QPACK prefixed-integer decoder cowhpackcommon:decbigint/3 in...

CVE-2026-64452 6lowpan: fix NHC entry use-after-free on error path

In the Linux kernel, the following vulnerability has been resolved: 6lowpan: fix NHC entry use-after-free on error path lowpannhcdouncompression looks up an NHC descriptor while holding lowpannhclock. If the descriptor has no uncompress callback, the error path drops the lock before printing...

PT-2026-64673

In the Linux kernel, the following vulnerability has been resolved: 6lowpan: fix NHC entry use-after-free on error path lowpan nhc do uncompression looks up an NHC descriptor while holding lowpan nhc lock. If the descriptor has no uncompress callback, the error path drops the lock before printing...

CVE-2026-54340

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 9265bdd, there is an HTTP/2 state amplification issue that combines HPACK decompression amplification with Slowloris-style stream stalling. Amplified decoded header state can be retained by stalled HTTP/2 streams,...

DEBIAN-CVE-2026-54340

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 9265bdd, there is an HTTP/2 state amplification issue that combines HPACK decompression amplification with Slowloris-style stream stalling. Amplified decoded header state can be retained by stalled HTTP/2 streams,...

UBUNTU-CVE-2026-54340

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 9265bdd, there is an HTTP/2 state amplification issue that combines HPACK decompression amplification with Slowloris-style stream stalling. Amplified decoded header state can be retained by stalled HTTP/2 streams,...

CVE-2026-54340

CVE-2026-54340 affects the h2o HTTP server (HTTP/2) and describes an HTTP/2 state amplification issue where HPACK decompression amplification combines with Slowloris-style stream stalling. Amplified decoded header state can be retained by stalled HTTP/2 streams; depending on configuration, additi...

CVE-2026-55204

A flaw was found in HAProxy. An attacker can trigger HPACK dynamic table insertions under memory pressure, leading to a null pointer dereference in the hpackdhtinsert function. This can cause HAProxy worker processes to crash, resulting in a denial of service DoS. Mitigation Mitigation for this...

CVE-2026-54428

A flaw was found in Apache HttpComponents Core. This vulnerability, located in the HTTP/2 HPACK decoder, allows a remote attacker to cause a denial of service. By sending oversized compressed header blocks, an attacker can exhaust memory resources before the system's configured header list size...

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...

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...