CVE-2023-27492 | Envoy may crash when a large request body is processed in Lua filter

Exp

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.

Published: 2023-04-04 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-27492 is rated Exploit Available (51.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.69%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-27492

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-27492

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.69% +0.65%
2 2025-03-30 0.14% 0.04% -0.10%
3 2025-03-29 — 0.14% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-27492

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.2 3.6 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2023-27492

OS Trackers for CVE-2023-27492

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2023-27492

Affected software / configurations for CVE-2023-27492

Vendor Product Version Raw CPE
envoyproxy envoy < 1.22.9 cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
envoyproxy envoy >= 1.23.0, < 1.23.6 cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
envoyproxy envoy >= 1.24.0, < 1.24.4 cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
envoyproxy envoy >= 1.25.0, < 1.25.3 cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*

References for CVE-2023-27492

cvelogic Threat Intelligence