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TI-2024-21369 Aliases CVE-2024-32475

Envoy RELEASE_ASSERT using auto_sni with :authority header > 255 bytes

Priority MEDIUM 40CWE-253Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-617.

Summary

Envoy is a cloud-native, open source edge and service proxy. When an upstream TLS cluster is used with `auto_sni` enabled, a request containing a `host`/`:authority` header longer than 255 characters triggers an abnormal termination of Envoy process. Envoy does not gracefully handle an error when setting SNI for outbound TLS connection. The error can occur when Envoy attempts to use the `host`/`:authority` header value longer than 255 characters as SNI for outbound TLS connection. SNI length is limited to 255 characters per the standard. Envoy always expects this operation to succeed and abnormally aborts the process when it fails. This vulnerability is fixed in 1.30.1, 1.29.4, 1.28.3, and 1.27.5.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00679 52nd percentileScored 2026-11-07
Fix Partial envoy (envoyproxy): 1.30.1, 1.29.4, 1.28.3 +1Red Hat: 2 advisoriesRed Hat: 2 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
envoyproxyenvoy1.30.0 to before 1.30.1; 1.29.0 to before 1.29.4; 1.28.0 to before 1.28.3; 1.13.0 to before 1.27.51.30.1, 1.29.4, 1.28.3, 1.27.5Patch availableCNA
  • envoy Vendorenvoyproxy Affected 1.30.0 to before 1.30.1; 1.29.0 to before 1.29.4; 1.28.0 to before 1.28.3; 1.13.0 to before 1.27.5 Fixed in 1.30.1, 1.29.4, 1.28.3, 1.27.5 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*1.13.0 to before 1.27.5; 1.28.0 to before 1.28.3; 1.29.0 to before 1.29.4Vulnerableenvoyproxy
cpe:2.3:a:envoyproxy:envoy:1.30.0:*:*:*:*:*:*:*1.30.0Vulnerableenvoyproxy
  • cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* Versions 1.13.0 to before 1.27.5; 1.28.0 to before 1.28.3; 1.29.0 to before 1.29.4 Vulnerable ·envoyproxy
  • cpe:2.3:a:envoyproxy:envoy:1.30.0:*:*:*:*:*:*:* Versions 1.30.0 Vulnerable ·envoyproxy

Remediation

  • Fix · CNA envoy (envoyproxy) Fixed in 1.30.1, 1.29.4, 1.28.3, 1.27.5

Red Hat 2 advisories

  • RHSA-2024:7725 Released 2024-10-07 · Red Hat rating Important
    Red Hat OpenShift Service Mesh Containers for 2.5.5
    • RHOSSM 2.5 for RHEL 8 openshift-service-mesh/grafana-rhel8, openshift-service-mesh/istio-cni-rhel8, openshift-service-mesh/istio-must-gather-rhel8 +5
  • RHSA-2024:7724 Released 2024-10-07 · Red Hat rating Important
    Red Hat OpenShift Service Mesh Containers for 2.4.11
    • RHOSSM 2.4 for RHEL 8 openshift-service-mesh/grafana-rhel8, openshift-service-mesh/istio-cni-rhel8, openshift-service-mesh/istio-must-gather-rhel8 +4

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
OpenShift Service Mesh 2AffectedNo fix planned: Will not fix
RHOSSM 2.4 for RHEL 8Fixed RHSA-2024:7724
RHOSSM 2.5 for RHEL 8Fixed RHSA-2024:7725

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-32475
  2. 2026-11-05 Affected versions changed · CNA

References

Patch 2

  • TI-2026-79288 Out-of-bounds write in Google Brotli decoder KEVCVSS 4.0CRITICAL 9.2
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2024-20001 HTTP/2: CPU exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
  • TI-2024-18524 HTTP/2: memory exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
  • TI-2023-12215 Envoy client may fake the header `x-envoy-original-path` CVSS 3.1CRITICAL 9.1
  • TI-2023-18002 Envoy vulnerable to OAuth2 credentials exploit with permanent validity CVSS 3.1CRITICAL 9.8
See all 126 →

Sources

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