7.5

CVE-2026-46340: netty

CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2026-46340DEBIAN-CVE-2026-46340CGA-29gf-xvc2-x7mg
Published 12-06-2026Last modified 18-09-2026
Open JSON

Vulnerability summary

CVE-2026-46340 is a high (CVSS 7.5) vulnerability in netty. EPSS estimates a 0.85% chance of exploitation in the next 30 days, higher than 57.6% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.85%
0%100%
Low · +0.24 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 5 · Related 3
OPENSUSE-SU-2026:11033-1RHSA-2026:53644RHSA-2026:53645RHSA-2026:53646SUSE-SU-2026:2802-1CGA-2764-7MMG-XGXX

Timeline

  1. 12-06-2026
    PublishedVulnerability first disclosed.
  2. 18-09-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.85%

Chance of exploitation in the next 30 days

Percentile

58%

Versus all other CVEs

30-day change

+0.24 pp

From 0.61% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.85%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard30 products
  • apache-hop< 2.18.0-r5
  • apache-hop-fips< 2.18.0-r4
  • celeborn-0.5< 0.5.4-r26
  • celeborn-0.6< 0.6.3-r8
  • hadoop-fips-3.3.6All versions (No fix recorded)
Wolfi18 products
  • celeborn-0.6< 0.6.3-r8
  • management-api-for-apache-cassandra-5.0< 0.1.120-r0
  • tez< 0.10.5-r16
  • thingsboard-tb-mqtt-transport< 4.3.1.2-r6
  • thingsboard-tb-node< 4.3.1.2-r6
Debian1 product
  • nettyAll versions (No fix recorded)
Io.netty1 product
  • netty-transport-sctp≥ 4.2.0.Final, < 4.2.15.Final | < 4.1.135.Final
Netty1 product
  • netty≥ 4.2.0.Final, < 4.2.15.Final | < 4.1.135.Final | < 4.1.135 | ≥ 4.2.0, < 4.2.15
Ubuntu1 product
  • nettyAll versions (No fix recorded)

6 vendors · 52 products

References

19 links
Show all 19 references