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Fencer Vulns
high 7.5

CVE-2026-46340 json

Netty: SCTP reassembly nests buffers without bound

published 2026-06-08 5 mo ago modified 2026-09-18 51 d ago also GHSA-5xrh-qmmq-w6ch , EUVD-2026-36451

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 49%
public exploits
0
none known

Summary

Netty is a network application framework for development of protocol servers and clients. In versions of netty-transport-sctp prior to 4.1.135.Final and 4.2.15.Final, for each non-complete SctpMessage fragment the handler does `fragments.put(streamId, Unpooled.wrappedBuffer(frag, byteBuf))`, wrapping the previous accumulator and the new slice into a *new* CompositeByteBuf every time. After N fragments the accumulator is an N-deep chain of composites, each holding references and component arrays; readableBytes()/getBytes() on the final buffer recurse N levels. There is no limit on N, on total bytes, or on the number of streamIdentifiers an attacker can open (each gets its own map entry). A peer that never sets the `complete` flag can grow this structure indefinitely from tiny 1-byte DATA chunks. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

Patch / fix

  • maven io.netty:netty-transport-sctp 4.1.135.Final, 4.2.15.Final
  • Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7 0:1.5.26-2.Final_redhat_00001.1.el7eap, 0:1.10.0-46.Final_redhat_00044.1.el7eap, 0:2.2.40-2.SP3_redhat_00001.1.el7eap, 0:2.3.14-11.SP11_redhat_00001.1.el7eap, 0:2.5.5-24.SP12_redhat_00016.1.el7eap, 0:2.5.5-30.SP12_redhat_00020.1.el7eap, 0:2.16.0-22.redhat_00057.1.el7eap, 0:2.18.8-1.redhat_00003.1.el7eap, 0:4.1.135-1.Final_redhat_00001.1.el7eap, 0:5.0.31-3.SP2_redhat_00001.1.el7eap, 0:7.4.25-2.GA_redhat_00001.1.el7eap
  • Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8 0:1.5.26-2.Final_redhat_00001.1.el8eap, 0:1.10.0-46.Final_redhat_00044.1.el8eap, 0:2.2.40-1.SP3_redhat_00001.1.el8eap, 0:2.3.14-11.SP11_redhat_00001.1.el8eap, 0:2.5.5-24.SP12_redhat_00016.1.el8eap, 0:2.5.5-30.SP12_redhat_00020.1.el8eap, 0:2.16.0-22.redhat_00057.1.el8eap, 0:2.18.8-1.redhat_00003.1.el8eap, 0:4.1.135-1.Final_redhat_00001.1.el8eap, 0:5.0.31-3.SP2_redhat_00001.1.el8eap, 0:7.4.25-2.GA_redhat_00001.1.el8eap
  • Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9 0:1.5.26-2.Final_redhat_00001.1.el9eap, 0:1.10.0-46.Final_redhat_00044.1.el9eap, 0:2.2.40-1.SP3_redhat_00001.1.el9eap, 0:2.3.14-11.SP11_redhat_00001.1.el9eap, 0:2.5.5-24.SP12_redhat_00016.1.el9eap, 0:2.5.5-30.SP12_redhat_00020.1.el9eap, 0:2.16.0-22.redhat_00057.1.el9eap, 0:2.18.8-1.redhat_00003.1.el9eap, 0:4.1.135-1.Final_redhat_00001.1.el9eap, 0:5.0.31-3.SP2_redhat_00001.1.el9eap, 0:7.4.25-2.GA_redhat_00001.1.el9eap
  • eap7-netty jboss enterprise application platform els 7.4 4.1.135-1.Final_redhat_00001.1.el8eap
  • eap7-wildfly jboss enterprise application platform els 7.4 7.4.25-2.GA_redhat_00001.1.el8eap
  • eap7-undertow jboss enterprise application platform els 7.4 2.2.40-1.SP3_redhat_00001.1.el8eap
  • eap7-netty-all jboss enterprise application platform els 7.4 4.1.135-1.Final_redhat_00001.1.el8eap
  • eap7-ironjacamar jboss enterprise application platform els 7.4 1.5.26-2.Final_redhat_00001.1.el8eap
  • eap7-netty-codec jboss enterprise application platform els 7.4 4.1.135-1.Final_redhat_00001.1.el8eap
  • eap7-jackson-core jboss enterprise application platform els 7.4 2.18.8-1.redhat_00003.1.el8eap
  • eap7-netty-buffer jboss enterprise application platform els 7.4 4.1.135-1.Final_redhat_00001.1.el8eap

red hat advisories RHSA-2026:53645RHSA-2026:53646RHSA-2026:53644

  • netty-tcnative SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.0.79-150200.3.45.1
  • netty SLE Module for Package Hub 15 SP7 4.1.135-150200.4.50.1

suse advisories SUSE-SU-2026:2802-1

  • netty openSUSE Tumbleweed 4.1.135-1.1

opensuse advisories openSUSE-SU-2026:11033-1

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-2026-46340 updated cvss 7.5

netty-transport-sctp: Netty-transport-sctp: Denial of Service due to unbounded memory growth from SctpMessage fragments

  • Red Hat Fuse 7 netty-transport-sctp
    affected: workaround, no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform 7 netty-transport-sctp
    affected: workaround, no fix available
  • Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16
    fixed: vendor fix RHSA-2026:37390
  • Red Hat Data Grid 8.6.2
    fixed: vendor fix RHSA-2026:41951
  • Red Hat JBoss EAP 7.4 ELS for RHEL 7 Server eap7-wildfly 7.4.25-2.GA_redhat_00001.1.el7eap, eap7-jackson-core 2.18.8-1.redhat_00003.1.el7eap, eap7-netty 4.1.135-1.Final_redhat_00001.1.el7eap, eap7-undertow 2.2.40-2.SP3_redhat_00001.1.el7eap, eap7-jackson-databind 2.18.8-1.redhat_00003.1.el7eap, eap7-netty-all 4.1.135-1.Final_redhat_00001.1.el7eap, +78 more
    fixed: vendor fix RHSA-2026:53644
  • Red Hat JBoss Enterprise Application Platform 7.4.25
    fixed: vendor fix RHSA-2026:53806
  • Red Hat Enterprise Linux AI (RHEL AI) 3 bazel6
    not affected: vulnerable code not present
  • Red Hat JBoss Enterprise Application Platform 8 netty-transport Red Hat JBoss Enterprise Application Platform Expansion Pack netty-transport-sctp
    not affected: component not present
show 1 more
  • Red Hat Single Sign-On 7 netty-transport-sctp
    not affected: vulnerable code not present

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

0.61% chance of exploitation in the next 30 days, higher than 49% 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-transport-sctp
>=4.2.0.Final, <4.2.15.Final
<4.1.135.Final
4.2.15.Final
4.1.135.Final

Affected products

  • netty netty
  • Red Hat Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16
  • Red Hat Red Hat Data Grid 8.6.2
  • Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7
  • Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8
  • Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9
  • Red Hat Red Hat JBoss Enterprise Application Platform 8.1
  • Red Hat Red Hat Enterprise Linux AI (RHEL AI) 3
  • Red Hat Red Hat Fuse 7
  • Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack
  • Red Hat Red Hat Single Sign-On 7

Classification

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

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.