CVE-2024-23327: envoy Null Dereference — Fix

Description

Envoy is a high-performance edge/middle/service proxy. When PPv2 is enabled both on a listener and subsequent cluster, the Envoy instance will segfault when attempting to craft the upstream PPv2 header. This occurs when the downstream request has a command type of LOCAL and does not have the protocol block. This issue has been addressed in releases 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.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
envoyproxy	envoy	1.26.0 — 1.26.7
envoyproxy	envoy	1.27.0 — 1.27.3
envoyproxy	envoy	1.28.0 — 1.28.1
envoyproxy	envoy	1.29.0 — 1.29.1

References

Advisories & Patches

https://github.com/envoyproxy/envoy/commit/63895ea8e3cca9c5d3ab4c5c128ed1369969d54a https://github.com/envoyproxy/envoy/commit/63895ea8e3cca9c5d3ab4c5c128ed1369969d54a

Other References

https://github.com/envoyproxy/envoy/security/advisories/GHSA-4h5x-x9vh-m29j https://github.com/envoyproxy/envoy/security/advisories/GHSA-4h5x-x9vh-m29j

Frequently Asked Questions

What is CVE-2024-23327? +

Envoy is a high-performance edge/middle/service proxy. When PPv2 is enabled both on a listener and subsequent cluster, the Envoy instance will segfault when attempting to craft the upstream PPv2 header. This occurs when the downstream request has a command type of LOCAL and does not have the protocol block. This issue has been addressed in releases 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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-23327? +

CVE-2024-23327 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-23327? +

CVE-2024-23327 affects products from envoyproxy, specifically: envoy. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-23327? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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