{"items":[{"id":"NVI-00008949","kind":"vulnerability","title":"Echo: Reverse Proxy Forwards Attacker-Supplied X-Real-IP to Upstream by Default","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-99jh-6h7p-pp36","CVE-2026-118651"],"plain_summary":"GitHub lists this reviewed advisory for github.com/labstack/echo/v5, github.com/labstack/echo/v4. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-42c9636fda8148630f36fcdefcb4b8a3"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-28T19:53:25.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-46f3594ccc85fab16d3a1a689a75c251"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.207%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.1081. Missing scores are unknown.","source_id":"sr-42c9636fda8148630f36fcdefcb4b8a3"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-46f3594ccc85fab16d3a1a689a75c251","url":"https://github.com/advisories/GHSA-99jh-6h7p-pp36","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-99jh-6h7p-pp36","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:36.327Z"},{"id":"sr-42c9636fda8148630f36fcdefcb4b8a3","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-118651","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.375Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-46f3594ccc85fab16d3a1a689a75c251"],"technology":"github.com/labstack/echo/v5","known_exclusions":[],"conditions_summary":"## Summary\n\nThe Echo proxy middleware (`middleware/proxy.go`) preserves an incoming `X-Real-IP` header verbatim and forwards it to the upstream service when `Echo#IPExtractor` is not configured — which is the default. Because any HTTP client can supply an arbitrary `X-Real-IP` value, an attacker can cause Echo to relay a spoofed client IP address to every upstream service behind the proxy, undermining upstream IP-based access controls, rate limiting, audit logging, and geo-restriction.\n\n## Affected Component\n\n- `middleware/proxy.go` — `ProxyConfig.ToMiddleware()`, header-rewriting block (lines 351–355)\n\n## Description\n\n### The header-preservation condition passes spoofed values to upstream\n\n`ProxyConfig.ToMiddleware()` (`proxy.go:338-405`) prepares forwarding headers before dispatching each request. The `X-Real-IP` rewrite logic at lines 351-355 reads:\n\n```go\n// proxy.go:351-355\n// Basically it's not good practice to unconditionally pass incoming x-real-ip header to upstream.\n// However, for backward compatibility, legacy behavior is preserved unless you configure Echo#IPExtractor.\nif req.Header.Get(echo.HeaderXRealIP) == \"\" || c.Echo().IPExtractor != nil {\n    req.Header.Set(echo.","public_affected_ranges":["< 5.4.0"]},{"certainty":"source_listed","source_ids":["sr-46f3594ccc85fab16d3a1a689a75c251"],"technology":"github.com/labstack/echo/v4","known_exclusions":[],"conditions_summary":"## Summary\n\nThe Echo proxy middleware (`middleware/proxy.go`) preserves an incoming `X-Real-IP` header verbatim and forwards it to the upstream service when `Echo#IPExtractor` is not configured — which is the default. Because any HTTP client can supply an arbitrary `X-Real-IP` value, an attacker can cause Echo to relay a spoofed client IP address to every upstream service behind the proxy, undermining upstream IP-based access controls, rate limiting, audit logging, and geo-restriction.\n\n## Affected Component\n\n- `middleware/proxy.go` — `ProxyConfig.ToMiddleware()`, header-rewriting block (lines 351–355)\n\n## Description\n\n### The header-preservation condition passes spoofed values to upstream\n\n`ProxyConfig.ToMiddleware()` (`proxy.go:338-405`) prepares forwarding headers before dispatching each request. The `X-Real-IP` rewrite logic at lines 351-355 reads:\n\n```go\n// proxy.go:351-355\n// Basically it's not good practice to unconditionally pass incoming x-real-ip header to upstream.\n// However, for backward compatibility, legacy behavior is preserved unless you configure Echo#IPExtractor.\nif req.Header.Get(echo.HeaderXRealIP) == \"\" || c.Echo().IPExtractor != nil {\n    req.Header.Set(echo.","public_affected_ranges":[">= 4.0.0, <= 4.16.2"]}],"null_published_at":"2026-10-31T23:18:17.220Z","source_updated_at":"2026-10-28T19:53:25.000Z","source_disclosed_at":"2026-10-28T19:53:24.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T21:56:36.327Z"},{"id":"NVI-00008949","kind":"vulnerability","title":"Echo: Reverse Proxy Forwards Attacker-Supplied X-Real-IP to Upstream by Default","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-99jh-6h7p-pp36","CVE-2026-118651"],"plain_summary":"GitHub lists this reviewed advisory for github.com/labstack/echo/v5, github.com/labstack/echo/v4. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-46f3594ccc85fab16d3a1a689a75c251"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-28T19:53:25.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-46f3594ccc85fab16d3a1a689a75c251"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-46f3594ccc85fab16d3a1a689a75c251","url":"https://github.com/advisories/GHSA-99jh-6h7p-pp36","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-99jh-6h7p-pp36","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:36.327Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-46f3594ccc85fab16d3a1a689a75c251"],"technology":"github.com/labstack/echo/v5","known_exclusions":[],"conditions_summary":"## Summary\n\nThe Echo proxy middleware (`middleware/proxy.go`) preserves an incoming `X-Real-IP` header verbatim and forwards it to the upstream service when `Echo#IPExtractor` is not configured — which is the default. Because any HTTP client can supply an arbitrary `X-Real-IP` value, an attacker can cause Echo to relay a spoofed client IP address to every upstream service behind the proxy, undermining upstream IP-based access controls, rate limiting, audit logging, and geo-restriction.\n\n## Affected Component\n\n- `middleware/proxy.go` — `ProxyConfig.ToMiddleware()`, header-rewriting block (lines 351–355)\n\n## Description\n\n### The header-preservation condition passes spoofed values to upstream\n\n`ProxyConfig.ToMiddleware()` (`proxy.go:338-405`) prepares forwarding headers before dispatching each request. The `X-Real-IP` rewrite logic at lines 351-355 reads:\n\n```go\n// proxy.go:351-355\n// Basically it's not good practice to unconditionally pass incoming x-real-ip header to upstream.\n// However, for backward compatibility, legacy behavior is preserved unless you configure Echo#IPExtractor.\nif req.Header.Get(echo.HeaderXRealIP) == \"\" || c.Echo().IPExtractor != nil {\n    req.Header.Set(echo.","public_affected_ranges":["< 5.4.0"]},{"certainty":"source_listed","source_ids":["sr-46f3594ccc85fab16d3a1a689a75c251"],"technology":"github.com/labstack/echo/v4","known_exclusions":[],"conditions_summary":"## Summary\n\nThe Echo proxy middleware (`middleware/proxy.go`) preserves an incoming `X-Real-IP` header verbatim and forwards it to the upstream service when `Echo#IPExtractor` is not configured — which is the default. Because any HTTP client can supply an arbitrary `X-Real-IP` value, an attacker can cause Echo to relay a spoofed client IP address to every upstream service behind the proxy, undermining upstream IP-based access controls, rate limiting, audit logging, and geo-restriction.\n\n## Affected Component\n\n- `middleware/proxy.go` — `ProxyConfig.ToMiddleware()`, header-rewriting block (lines 351–355)\n\n## Description\n\n### The header-preservation condition passes spoofed values to upstream\n\n`ProxyConfig.ToMiddleware()` (`proxy.go:338-405`) prepares forwarding headers before dispatching each request. The `X-Real-IP` rewrite logic at lines 351-355 reads:\n\n```go\n// proxy.go:351-355\n// Basically it's not good practice to unconditionally pass incoming x-real-ip header to upstream.\n// However, for backward compatibility, legacy behavior is preserved unless you configure Echo#IPExtractor.\nif req.Header.Get(echo.HeaderXRealIP) == \"\" || c.Echo().IPExtractor != nil {\n    req.Header.Set(echo.","public_affected_ranges":[">= 4.0.0, <= 4.16.2"]}],"null_published_at":"2026-10-31T22:13:27.124Z","source_updated_at":"2026-10-28T19:53:25.000Z","source_disclosed_at":"2026-10-28T19:53:24.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-10-31T21:56:36.327Z"}],"next_cursor":null,"snapshot_revision":"42594"}