CVE-2026-26310 Crash for scoped ip address in Envoy during DNS

What is CVE-2026-26310?

CVE-2026-26310 is a medium-severity denial of service vulnerability in Envoyproxy Envoy, published on 10 Mar 2026. An attacker can exploit it over the internet without logging in, 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, calling Utility::getAddressWithPort with a scoped IPv6 addresses causes a crash. This utility is called in the data plane from the original_src filter and the dns filter. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.

Weakness: CWE-20

Which versions are affected by CVE-2026-26310?

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

Products include Envoyproxy Envoy.

How do I fix CVE-2026-26310?

Upgrade to a fixed version.

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-2026-26310 being exploited?

There is no known exploitation of CVE-2026-26310 in the wild and no public exploit code.

Other vulnerabilities in Envoyproxy Envoy

• CVE-2022-29226 Trivial authentication bypass in Envoy Critical 10.0
• CVE-2019-18801 Memory corruption in n/a Critical 9.8
• CVE-2019-18802 Security feature bypass in n/a Critical 9.8
• CVE-2020-35470 Information disclosure in n/a High 8.8
• CVE-2024-23324 Envoy ext auth can be bypassed when Proxy protocol filter sets invalid UTF-8 metadata High 8.6

All Envoyproxy Envoy vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-envoy-2026-26310, GHSA-3cw6-2j68-868p.