CVE-2026-55233

OpenResty is a high performance web platform. From 1.29.2.1 to before 1.29.2.5, an out-of-bounds write vulnerability exists in the upstream PROXY protocol v2 implementation. When OpenResty is configured to send PROXY protocol version 2 headers to upstream servers, constructing the header in the stream proxy protocol v2 patch can write beyond the bounds of the allocated buffer, causing the worker process to crash and resulting in a denial of service. Only configurations that explicitly enable PROXY protocol v2 for upstream connections are impacted. This issue is fixed in version 1.29.2.5.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/openresty/openresty/commit/5c56ad2958a2dad8b2cc99f4987b8642cbc647d1	Patch
https://github.com/openresty/openresty/security/advisories/GHSA-wx83-v28q-68gx	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openresty:openresty:*:*:*:*:*:*:*:*

History

14 Jul 2026, 19:20

Type	Values Removed	Values Added
First Time		Openresty openresty Openresty
References	~~() https://github.com/openresty/openresty/commit/5c56ad2958a2dad8b2cc99f4987b8642cbc647d1 -~~	() https://github.com/openresty/openresty/commit/5c56ad2958a2dad8b2cc99f4987b8642cbc647d1 - Patch
References	~~() https://github.com/openresty/openresty/security/advisories/GHSA-wx83-v28q-68gx -~~	() https://github.com/openresty/openresty/security/advisories/GHSA-wx83-v28q-68gx - Mitigation, Vendor Advisory
CPE		cpe:2.3:a:openresty:openresty::::::::

10 Jul 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-10 21:16

Updated : 2026-07-14 19:20

NVD link : CVE-2026-55233

Mitre link : CVE-2026-55233

CVE.ORG link : CVE-2026-55233

JSON object : View

Products Affected

openresty

openresty

CWE

CWE-787

Out-of-bounds Write

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