Description

An attacker may cause an HTTP/2 endpoint to read arbitrary amounts of header data by sending an excessive number of CONTINUATION frames. Maintaining HPACK state requires parsing and processing all HEADERS and CONTINUATION frames on a connection. When a request's headers exceed MaxHeaderBytes, no memory is allocated to store the excess headers, but they are still parsed. This permits an attacker to cause an HTTP/2 endpoint to read arbitrary amounts of header data, all associated with a request which is going to be rejected. These headers can include Huffman-encoded data which is significantly more expensive for the receiver to decode than for an attacker to send. The fix sets a limit on the amount of excess header frames we will process before closing a connection.

Severity HIGH

CVSS Score 8.0

CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE N/A

Public Exploit ✅ No

Source NVD

Published 2024-04-06

Updated 2026-06-15

Modified 2026-01-28

Fix URL N/A

Software	From version	Fixed in
golang	—	—
golang.org/x/net	—	—
golang.org/x/net/http2	—	—
net/http	—	—
newrelic-fluent-bit-output	—	1.19.2-r2
stdlib	—	—
unknown	—	—
vault-fips-1.14	—	1.14.10-r0