CVE-2026-48497: Envoy: Abnormal process termination in DNS UDP filter
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, in cases where UDP DNS filter is configured with local resolution containing a name with the length of 255 octets or remote resolution for a name of 255 octets long can complete successfully, a query with such name will result in abnormal process termination. The abnormal process termination is triggered by an invalid runtime precondition that the query name is strictly less than 255 octets, contradicting DNS specification rfc1035#section-2.3.4 that the name can be 255 or less octets. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Envoyto a version that resolves this vulnerability.Fixed in 1.35.11 - Upgrade
Upgrade
Envoyto a version that resolves this vulnerability.Fixed in 1.36.7 - Upgrade
Upgrade
Envoyto a version that resolves this vulnerability.Fixed in 1.37.3 - Upgrade
Upgrade
Envoyto a version that resolves this vulnerability.Fixed in 1.38.1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-48497?
The severity of CVE-2026-48497 is medium with a CVSS score of 5.9.
What does CVE-2026-48497 affect?
CVE-2026-48497 affects the Envoy edge and service proxy applications.
How do I fix CVE-2026-48497?
To fix CVE-2026-48497, upgrade Envoy to version 1.35.11, 1.36.7, 1.37.3, or 1.38.1 or later.
What causes the vulnerability in CVE-2026-48497?
CVE-2026-48497 is caused by abnormal process termination when the UDP DNS filter is configured with a name that is 255 octets long.
Is remote resolution affected by CVE-2026-48497?
Yes, both local and remote resolutions are affected by CVE-2026-48497 when handling names of 255 octets in length.