## Echo has Open Redirect via Control-Character Prefix Defeating sanitizeURI

- 種別: advisory
- 重大度: medium
- 関連技術: go, github
- CVE: CVE-2026-118656
- 公開日時: 2026-10-28T21:04:22.000Z
- 情報源: GitHub Advisory Database (https://github.com/advisories/GHSA-v753-g4cw-jm48)
- パーマリンク: https://vulnpulse.app/items/ghsa-ghsa-v753-g4cw-jm48

影響: go:github.com/labstack/echo/v5 < 5.4.0 → 5.4.0, go:github.com/labstack/echo/v4 < 4.16.0 → 4.16.0
Echo's dedicated open-redirect guard, sanitizeURI, decides whether a redirect target is a local path by inspecting exactly two byte positions: uri[0] and uri[1]. If the value begins with a control character such as a tab or a newline, followed by a separator pair, the guard does not fire and the value is written to the Location header unchanged. Browsers remove tab and newline characters from URLs before parsing them, and treat a backslash as a forward slash for HTTP and HTTPS URLs. A Location…