CVE-2026-55233

highCVSS 7.5covered by 1 sourcefirst seen 2026-07-10

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.

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Advisory coverage (1)

highCVE-2026-55233: OpenResty is a high performance web platform. From 1.29.2.1 to before 1.29.2.5, an out-of-boun…nvd · 2026-07-10

External references

NVD record for CVE-2026-55233

CVE.org record

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