Findings

CVE-2026-39825

ReverseProxy can forward queries containing parameters not visible to Rewrite functions.

Published May 7, 2026 · updated Jun 17, 2026 · golang go

ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a Rewrite function, or a Director function which parses query parameters, ReverseProxy sanitizes the forwarded request to remove query parameters which are not parsed by url.ParseQuery. ReverseProxy does not take ParseQuery's limit on the total number of query parameters (controlled by GODEBUG=urlmaxqueryparams=N) into account. This can permit ReverseProxy to forward a request containing a query parameter that is not visible to the Rewrite function. For example, the query "a1=x&a2=x&...&a10000=x&hidden=y" can forward the parameter "hidden=y" while hiding it from the proxy's Rewrite function.

Code

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No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. May 7, 2026 · NIST NVD

    Detected

    ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a Rewrite function, or a Director function which parses query parameters, ReverseProxy sanitizes the forwarded request to remove query parameters which are not parsed by url.ParseQuery. ReverseProxy does not take ParseQuery's limit on the total number of query parameters (controlled by GODEBUG=u

  2. Jun 17, 2026 · NIST NVD

    Updated

    ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a Rewrite function, or a Director function which parses query parameters, ReverseProxy sanitizes the forwarded request to remove query parameters which are not parsed by url.ParseQuery. ReverseProxy does not take ParseQuery's limit on the total number of query parameters (controlled by GODEBUG=u

Affected

  • cpe golang/goversion unspecified

Sources

  • CVE.orgVulnerability recordCVE-2026-39825

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2026-39825

    ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a Rewrite function, or a Director function which parses query parameters, ReverseProxy sanitizes the forwarded request to remove query parameters which are not parsed by url.Pa

    nvd.nist.gov

References