CVE-2025-62504

Oct. 16, 2025, 10:15 p.m.

6.5
Medium

Description

Envoy is an open source edge and service proxy. Envoy versions earlier than 1.36.2, 1.35.6, 1.34.10, and 1.33.12 contain a use-after-free vulnerability in the Lua filter. When a Lua script executing in the response phase rewrites a response body so that its size exceeds the configured per_connection_buffer_limit_bytes (default 1MB), Envoy generates a local reply whose headers override the original response headers, leaving dangling references and causing a crash. This results in denial of service. Updating to versions 1.36.2, 1.35.6, 1.34.10, or 1.33.12 fixes the issue. Increasing per_connection_buffer_limit_bytes (and for HTTP/2 the initial_stream_window_size) or increasing per_request_buffer_limit_bytes / request_body_buffer_limit can reduce the likelihood of triggering the condition but does not correct the underlying memory safety flaw.

Product(s) Impacted

Vendor Product Versions
Envoy
  • Envoy
  • <1.36.2, <1.35.6, <1.34.10, <1.33.12

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-416
Use After Free
Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a envoy envoy <1.36.2 / / / / / / /
a envoy envoy <1.35.6 / / / / / / /
a envoy envoy <1.34.10 / / / / / / /
a envoy envoy <1.33.12 / / / / / / /

CVSS Score

6.5 / 10

CVSS Data - 3.1

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Privileges Required: LOW
  • Scope: UNCHANGED
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: HIGH
  • CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

    View Vector String

Timeline

Published: Oct. 16, 2025, 10:15 p.m.
Last Modified: Oct. 16, 2025, 10:15 p.m.

Status : Received

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

security-advisories@github.com

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.