CNCF Envoy through 1.13.0 may consume excessive amounts of memory when proxying HTTP/1.1 requests or responses with many small (i.e. 1 byte) chunks.
Conclusion & alert: CVE-2020-8659 is rated Moderate Risk (56.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.02%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2025-11-21 | 1.06% | 1.02% | -0.05% |
| 2 | 2025-11-18 | 1.03% | 1.06% | +0.04% |
| 3 | 2025-07-19 | — | 1.03% | — |
Full EPSS history (17 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2020-8659 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| cncf | envoy | <= 1.13.0 | cpe:2.3:a:cncf:envoy:*:*:*:*:*:*:*:* |
| redhat | openshift_service_mesh | 1.0 | cpe:2.3:a:redhat:openshift_service_mesh:1.0:*:*:*:*:*:*:* |
| debian | debian_linux | 9.0 | cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://access.redhat.com/errata/RHSA-2020:0734 | Third Party Advisory |
| https://github.com/envoyproxy/envoy/security/advisories/GHSA-jwcm-4pwp-c2qv | Third Party Advisory |
| https://lists.debian.org/debian-lts-announce/2022/05/msg00025.html | Mailing List Third Party Advisory |
| https://www.envoyproxy.io/docs/envoy/v1.13.1/intro/version_history | Release Notes Third Party Advisory |