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

> Attackers can crash Envoy proxy by triggering a use-after-free in the rate limit filter when response phase limits are enabled and fail.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Mar 2026
- **Updated:** 10 Mar 2026
- **Also known as:** BIT-envoy-2026-26330, GHSA-c23c-rp3m-vpg3

## What is CVE-2026-26330?

CVE-2026-26330 is a medium-severity use after free vulnerability in Envoyproxy Envoy, published on 10 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official 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.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-26330?

5 open source packages ship an affected version, including github.com/envoyproxy/envoy and envoy. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/envoyproxy/envoy` | Go | All versions | None |
| `github.com/envoyproxy/envoy` | Go | All versions | None |
| `github.com/envoyproxy/envoy` | Go | From 1.36.0 to 1.36.4 | None |
| `github.com/envoyproxy/envoy` | Go | From 1.36.0 to 1.36.4 | None |
| `envoy` | Bitnami | All versions | 1.34.13, 1.35.9, 1.36.5, 1.37.1 |

Products: Envoyproxy Envoy.

## How do I fix CVE-2026-26330?

Upgrade to a fixed version.

## Is CVE-2026-26330 being exploited?

There is no known exploitation of CVE-2026-26330 in the wild and no public exploit code.

## Other vulnerabilities in Envoyproxy Envoy

- [CVE-2022-29226](https://insights.sbomify.com/CVE-2022-29226/): Trivial authentication bypass in Envoy (critical 10.0)
- [CVE-2019-18801](https://insights.sbomify.com/CVE-2019-18801/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-18802](https://insights.sbomify.com/CVE-2019-18802/): Security feature bypass in n/a (critical 9.8)
- [CVE-2020-35470](https://insights.sbomify.com/CVE-2020-35470/): Information disclosure in n/a (high 8.8)
- [CVE-2024-23324](https://insights.sbomify.com/CVE-2024-23324/): Envoy ext auth can be bypassed when Proxy protocol filter sets invalid UTF-8 metadata (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-26330 and fix it if it is affected.

What it is: CVE-2026-26330 is a medium-severity use after free vulnerability in Envoyproxy Envoy, published on 10 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-26330 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/envoyproxy/envoy (Go): affected all versions; no fix listed
- github.com/envoyproxy/envoy (Go): affected all versions; no fix listed
- github.com/envoyproxy/envoy (Go): affected from 1.36.0 up to 1.36.4; no fix listed
- github.com/envoyproxy/envoy (Go): affected from 1.36.0 up to 1.36.4; no fix listed
- envoy (Bitnami): affected all versions; fixed in 1.34.13, 1.35.9, 1.36.5, 1.37.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-26330/ (Markdown: https://insights.sbomify.com/CVE-2026-26330/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-26330
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-26330
- OSV: https://osv.dev/vulnerability/CVE-2026-26330

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-26330/
Summaries are generated and may contain mistakes; the official description above is the record.