7.5

CVE-2026-56819: netty Uncontrolled Resource Consumption

CVSS: 7.5v3.1HighAnalyzed
AliasesUBUNTU-CVE-2026-56819DEBIAN-CVE-2026-56819CGA-2f6g-fhxm-wv6j
Published 21-07-2026Last modified 23-07-2026
Open JSON

Vulnerability summary

CVE-2026-56819 is a high (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in netty. EPSS estimates a 0.66% chance of exploitation in the next 30 days, higher than 50.8% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
40/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.66%
0%100%
Low · +0.22 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 2 · Related 3
OPENSUSE-SU-2026:11394-1SUSE-SU-2026:3482-1CGA-H2FM-MV6F-9GVC

Timeline

  1. 21-07-2026
    PublishedVulnerability first disclosed.
  2. 23-07-2026
    Last modifiedVulnerability information updated.

Description

Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, a remote unauthenticated peer can leak one direct `ByteBuf` per HTTP/2 `DATA` frame in applications that enable HTTP/2 content decompression via `DelegatingDecompressorFrameListener`. When a `DATA` frame is processed for a stream whose decompressor has already been closed, `Http2Decompressor.decompress(...)` calls `decompressor.writeInbound(data.retain())` and does not release the retained buffer on the error path, eventually exhausting direct memory and crashing the JVM. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.66%

Chance of exploitation in the next 30 days

Percentile

51%

Versus all other CVEs

30-day change

+0.22 pp

From 0.44% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.66%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Netty

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Chainguard93 products
  • apache-camel-karavan-devmode< 4.18.1-r8
  • apache-pulsar-4.1< 4.1.3-r15
  • apache-pulsar-fips-4.1All versions (No fix recorded)
  • camunda-zeebe-8.6< 8.6.39-r6
  • celeborn-0.5All versions (No fix recorded) | < 0.5.4-r32
Wolfi25 products
  • apache-pulsar-4.1< 4.1.3-r15
  • celeborn-0.6All versions (No fix recorded) | < 0.6.3-r13
  • druid< 37.0.0-r47 | < 37.0.0-r56 | < 37.0.0-r46
  • keycloak-26.5All versions (No fix recorded)
  • keycloak-26.5-iamguarded-compatAll versions (No fix recorded)
Debian1 product
  • nettyAll versions (No fix recorded)
Io.netty1 product
  • netty-codec-http2≥ 4.2.0, < 4.2.16.Final | ≥ 4.1.0.Final, < 4.1.136.Final
Netty1 product
  • netty≥ 4.2.0.Final, < 4.2.16.Final | ≥ 4.1.0.Final, < 4.1.136.Final | ≥ 4.1.0, < 4.1.136 | ≥ 4.2.0, < 4.2.16
Ubuntu1 product
  • nettyAll versions (No fix recorded)

6 vendors · 122 products

References

11 links
Show all 11 references