High severity · published Jun 12, 2026
CVE-2026-48748
Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Netty is a network application framework for development of protocol servers and clients. Starting in version 4.2.0.Final and prior to version 4.2.15.Final, a memory exhaustion vulnerability in the Netty HTTP/3 codec allows the creation of an infinite number of blocked streams, which can cause OOM error. Version 4.2.15.Final patches the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
netty · netty
>= 4.2.0.Final, < 4.2.15.Final · source: vendor, NVD
RH
Red Hat build of Apache Camel - HawtIO 4 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-48748
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-48748
github.com
https://github.com/netty/netty/commit/75127cab731ee35068d1f0667bffa188bc332f5d
Release Notes
https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
Vendor Advisory
https://github.com/netty/netty/security/advisories/GHSA-4grm-h2qv-h6w6
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-48748
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2488441
security.access.redhat.com
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48748.json
More from netty
7.5
CVE-2023-44487
HTTP/2 Rapid Reset Attack Vulnerability
10.0
CVE-2026-47691
Netty has Insufficient Bailiwick Validation for NS Records
10.0
CVE-2026-45674
Netty Vulnerable to DNS Cache Poisoning via Missing Bailiwick Checks in CNAME Records
9.8
CVE-2026-56817
Netty: XML External Entity (XXE) injection via unconfigured XML factory when DTD and entity processing are enabled
9.8
CVE-2026-42581
Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization