An issue was discovered in Envoy 1.12.0.
Priority MEDIUM 47Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
An issue was discovered in Envoy 1.12.0. An untrusted remote client may send an HTTP header (such as Host) with whitespace after the header content. Envoy will treat "header-value " as a different string from "header-value" so for example with the Host header "example.com " one could bypass "example.com" matchers.
Why it matters now
EPSS 0.02457 84th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed Red Hat: 1 advisory
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* | up to 1.12.1 | Vulnerable | envoyproxy |
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* Versions up to 1.12.1 Vulnerable ·envoyproxy
Remediation
Red Hat 1 advisory
- RHSA-2019:4222 Released 2019-12-11 · Red Hat rating CriticalRed Hat OpenShift Service Mesh 1.0.3 RPMs security update
- OpenShift Service Mesh 1.0 servicemesh-1.0.3-1.el8, servicemesh-citadel-1.0.3-1.el8, servicemesh-cni-1.0.3-1.el8 +12
- Red Hat OpenShift Service Mesh 1.0 kiali-v1.0.8.redhat1-1.el7
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| OpenShift Service Mesh 1.0 | Fixed | RHSA-2019:4222 |
| Red Hat OpenShift Service Mesh 1.0 | Fixed | RHSA-2019:4222 |
Timeline
- 2026-10-02 Threatist record created from CVE-2019-18802
- 2026-10-03 Alias added: GHSA-fx83-72pw-c56f
References
More envoyproxy Envoy vulnerabilities
- 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
Sources
- CVE-2019-18802 · CVE Program
- CVE-2019-18802 · NVD
- FIRST EPSS
- GHSA-fx83-72pw-c56f · GitHub Advisory Database · CC BY 4.0
- CVE-2019-18802 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences