Allocation of Resources Without Limits or Throttling in Netty - CVE-2026-48748
Published: June 8, 2026
Vulnerability identifier: #VU133442
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-48748
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Netty project
Affected software:
Netty
Netty
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to allocation of resources without limits or throttling in io.netty.handler.codec.http3.QpackDecoder#shouldWaitForDynamicTableUpdates when processing HTTP/3 header blocks that reference dynamic table entries the server has not yet received. A remote attacker can send specially crafted HTTP/3 requests to cause a denial of service.
Only servers with QPACK dynamic tables enabled are vulnerable when the blocked streams setting is left at its default value of 0.
How to mitigate CVE-2026-48748
Install security update from vendor's website.