Echo: X-Real-IP extractor trusts the header value instead of the sending peer

[ Description ]Official description

Echo is a Go web framework. From 5.0.0 until 5.4.1, Echo v5's ExtractIPFromRealIPHeader validates whether the client-supplied X-Real-IP value belongs to a trusted range instead of validating the direct network peer. A client reaching Echo directly, or through a proxy that preserves the header, can supply a loopback or private address and have Context.RealIP return that spoofed identity. Applications using the extractor for IP allowlists, rate limiting, audit logs, or forwarding headers can consequently trust an attacker-controlled address; the default direct extractor and Echo v4 are unaffected. This issue is fixed in 5.4.1.

[ Fixes ]Fixes and patches

• github.com/labstack/echo/v5 5.4.1Fixed version · GitHub Advisories · go package github.com/labstack/echo/v5: upgrade to 5.4.1 or later (affected >= 5.0.0, < 5.4.1)

[ Packages ]Affected open-source packages

• github.com/labstack/echo/v5 goAffected >= 5.0.0, < 5.4.1 · fixed in 5.4.1 · GHSA-h53f-rm2w-w7rg

[ References ]References

• github.com/labstack/echo/commit/1855061e572ae9dab727c811d8382f266bfbaae
• github.com/labstack/echo/releases/tag/v5.4.1
• github.com/labstack/echo/security/advisories/GHSA-h53f-rm2w-w7rg