CVE-2023-27492 - CVE House
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Status published Medium CVE-2023-27492

Envoy may crash when a large request body is processed in Lua filter

Vulnerability Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, the Lua filter is vulnerable to denial of service. Attackers can send large request bodies for routes that have Lua filter enabled and trigger crashes. As of versions versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, Envoy no longer invokes the Lua coroutine if the filter has been reset. As a workaround for those whose Lua filter is buffering all requests/ responses, mitigate by using the buffer filter to avoid triggering the local reply in the Lua filter.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

envoy
Vulnerable Versions:
>= 1.25.0, < 1.25.3, >= 1.24.0, < 1.24.4, >= 1.23.0, < 1.23.6, < 1.22.9

Timeline

Official Publish: April 4th, 2023
Last Modified: February 11th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-770

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact
T1190 Exploit Public-Facing Application
Initial Access
T1562 Impair Defenses
Defense Evasion
T1046 Network Service Discovery
Discovery