Vulnerability Description
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 Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Openresty | Openresty | >= 1.29.2.1, < 1.29.2.5 |
Related Weaknesses (CWE)
References
- https://github.com/openresty/openresty/commit/5c56ad2958a2dad8b2cc99f4987b8642cbPatch
- https://github.com/openresty/openresty/security/advisories/GHSA-wx83-v28q-68gxMitigationVendor Advisory
FAQ
What is CVE-2026-55233?
CVE-2026-55233 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 configur...
How severe is CVE-2026-55233?
CVE-2026-55233 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-55233?
Check the references section above for vendor advisories and patch information. Affected products include: Openresty Openresty.