CVE-2024-23323

Excessive CPU usage when URI template matcher is configured using regex in Envoy

MEDIUM

5.3

CVSS Score

Published: February 9, 2024 at 10:50 PM UTC

Updated: June 17, 2026 at 07:12 AM UTC

1 product affected across 1 vendorEnvoy

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Severity

MEDIUM5.3

Exploit prediction

EPSS 0.5%

SSVC

No known exploit

Description

Envoy is a high-performance edge/middle/service proxy. The regex expression is compiled for every request and can result in high CPU usage and increased request latency when multiple routes are configured with such matchers. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Affected

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

Envoy · Envoyproxy

95%

v < 1.26.7v < 1.27.3v < 1.28.1v < 1.29.11.26.0 ≤ v < 1.26.71.27.0 ≤ v < 1.27.31.28.0 ≤ v < 1.28.11.29.0 ≤ v < 1.29.1

Affected range stops below 1.26.7, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.27.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.28.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 1.29.1, 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:

Patch and advisory references

References (2)

x_refsource_MISCPatchVendor Advisory

Source: [email protected]

https://github.com/envoyproxy/envoy/commit/71eeee8f0f0132f39e402b0ee23b361ee2f4e645

x_refsource_CONFIRMVendor Advisory

Source: [email protected]

https://github.com/envoyproxy/envoy/security/advisories/GHSA-x278-4w4x-r7ch

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

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

CVSS

5.3MEDIUM[email protected]

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

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-400CWE-1176

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