CVE-2024-32475 Envoy RELEASE_ASSERT using auto_sni with :authority header > 255 bytes
Attackers can crash Envoy proxy by sending long authority headers when auto_sni is enabled, causing service disruption.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-32475?
CVE-2024-32475 is a high-severity denial of service vulnerability in Envoyproxy Envoy, published on 18 Apr 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2024-32475?
1 open source package ship an affected version, including envoy. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
envoy Bitnami | From 1.13.0 | 1.27.5, 1.28.3, 1.29.4, 1.30.1 |
Products include Envoyproxy Envoy.
How do I fix CVE-2024-32475?
Upgrade envoy to a fixed version for your release line: 1.27.5, 1.28.3, 1.29.4 or 1.30.1.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-32475 being exploited?
There is no known exploitation of CVE-2024-32475 in the wild and no public exploit code.
Other vulnerabilities in Envoyproxy Envoy
Sources
Also known as BIT-envoy-2024-32475, GHSA-3mh5-6q8v-25wj.