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TI-2026-42715 Aliases CVE-2026-59901GHSA-558v-64gr-wgg4

Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang

Priority MEDIUM 44CWE-835Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 3 fixed, 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-835.

Summary

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, the `Bzip2Decoder` handler in Netty's compression codec pipeline is vulnerable to a denial-of-service attack through a malformed bzip2 stream that permanently captures the event-loop thread in an infinite loop. The vulnerability exists in the run-length encoding (RLE) state machine within [`Bzip2BlockDecompressor.read()`]. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0046 40th percentileScored 2026-11-07
Fix Partial netty (netty): 4.2.16.Final, 4.1.136.Finalio.netty:netty-codec-compression (Maven): 4.2.16.Final+1 more productRed Hat: 3 advisoriesRed Hat: 3 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nettynetty4.2.0.Final to before 4.2.16.Final; before 4.1.136.Final4.2.16.Final, 4.1.136.FinalPatch availableCNA
—io.netty:netty-codec-compression (Maven)4.2.0.Final to before 4.2.16.Final4.2.16.FinalPatch availableGHSA-558v-64gr-wgg4
—io.netty:netty-codec (Maven)before 4.1.136.Final4.1.136.FinalPatch availableGHSA-558v-64gr-wgg4
  • netty Vendornetty Affected 4.2.0.Final to before 4.2.16.Final; before 4.1.136.Final Fixed in 4.2.16.Final, 4.1.136.Final Patch available CNA
  • io.netty:netty-codec-compression (Maven) Vendor— Affected 4.2.0.Final to before 4.2.16.Final Fixed in 4.2.16.Final Patch available GHSA-558v-64gr-wgg4
  • io.netty:netty-codec (Maven) Vendor— Affected before 4.1.136.Final Fixed in 4.1.136.Final Patch available GHSA-558v-64gr-wgg4

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*before 4.1.136; 4.2.0 to before 4.2.16Vulnerablenetty
  • cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* Versions before 4.1.136; 4.2.0 to before 4.2.16 Vulnerable ·netty

Remediation

  • Fix · CNA netty (netty) Fixed in 4.2.16.Final, 4.1.136.Final
  • Fix · GHSA-558v-64gr-wgg4 io.netty:netty-codec-compression (Maven) Fixed in 4.2.16.Final Advisory →
  • Fix · GHSA-558v-64gr-wgg4 io.netty:netty-codec (Maven) Fixed in 4.1.136.Final Advisory →

Red Hat 3 advisories

  • RHSA-2026:90321 Released 2026-10-26 · Red Hat rating Critical
    Red Hat OpenShift Dev Spaces 3.31.0 Release.
    • Red Hat OpenShift Dev Spaces 3.31 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/jetbrains-ide-rhel9 +8
  • RHSA-2026:69296 Released 2026-09-21 · Red Hat rating Important
    Red Hat Data Grid 8.6.3 security update
    • Red Hat Data Grid 8.6.3
  • RHSA-2026:54435 Released 2026-08-12 · Red Hat rating Important
    Streams for Apache Kafka 3.2.1 release and security update
    • Streams for Apache Kafka 3.2.1

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat build of Apache Camel - HawtIO 4AffectedNo fix yet
Red Hat Data Grid 8.6.3Fixed RHSA-2026:69296
Red Hat OpenShift Dev Spaces 3.31Fixed RHSA-2026:90321
Streams for Apache Kafka 3.2.1Fixed RHSA-2026:54435
Not affected: 3 products
  • Red Hat JBoss Enterprise Application Platform Expansion Pack
  • Red Hat OpenShift Dev Spaces
  • Red Hat OpenShift Dev Spaces 3.31

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-59901
  2. 2026-10-03 Alias added: GHSA-558v-64gr-wgg4
  3. 2026-10-29 Fix available: Red Hat OpenShift Dev Spaces 3.31 · Red Hat
  4. 2026-10-30 Fix available: RHSA-2026:90321 · Red Hat

References

Advisory 1

Other 3

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2026-30861 Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization CVSS 3.1CRITICAL 9.8
  • TI-2026-30864 Netty: HttpClientCodec response desynchronization CVSS 3.1CRITICAL 9.1
  • TI-2026-30859 Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder) CVSS 3.1CRITICAL 9.1
  • TI-2026-40973 Netty: Missing CertificateID Validation in OCSP Response Allows Replay Attacks CVSS 3.1CRITICAL 9.1
  • TI-2026-40972 Uncontrolled resource consumption in netty CVSS 3.1HIGH 7.5
See all 92 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences