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Fencer Vulns
high 7.5

CVE-2026-48748 json

Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion

published 2026-06-12 4 mo ago modified 2026-09-10 1 mo ago also GHSA-4grm-h2qv-h6w6 , EUVD-2026-36459

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits
0
none known

Summary

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.

Patch / fix

  • maven io.netty:netty-codec-http3 4.2.15.Final
  • netty netty 4.2.15

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-48748 updated cvss 7.5

netty: Netty: Denial of Service due to memory exhaustion in HTTP/3 codec

  • Red Hat build of Apache Camel - HawtIO 4 netty-codec-http3
    under investigation

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
4 mo ago

Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
maven io.netty:netty-codec-http3
>=4.2.0.Final, <4.2.15.Final
4.2.15.Final

Affected products

  • netty netty
  • Red Hat Red Hat build of Apache Camel - HawtIO 4

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.