CVE-2023-27492

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

MEDIUM
6.5
CVSS Score
Published: April 4, 2023 at 06:34 PM UTC
Updated: June 17, 2026 at 05:45 AM UTC
1 product affected across 1 vendorEnvoy

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.7%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.22.9v < 1.23.6v < 1.24.4v < 1.25.31.23.0 ≤ v < 1.23.61.24.0 ≤ v < 1.24.41.25.0 ≤ v < 1.25.3
Affected range stops below 1.22.9, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.23.6, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.24.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.25.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-770

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