{"items":[{"id":"NVI-00008845","kind":"vulnerability","title":"Echo has Open Redirect via Control-Character Prefix Defeating sanitizeURI","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-v753-g4cw-jm48","CVE-2026-118656"],"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-1136a1bde8530a4f810aedbcf9196ec5"],"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":"2026-10-28T21:04:23.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-007059983e5e0c9edbb3066f00e88379"},{"kind":"CVSS","as_of":"2026-10-29T18:17:27.827Z","value":"6.1 MEDIUM (3.1)","meaning":"security-advisories@github.com severity; no combined Null risk score.","source_id":"sr-1c20295bbf928148ccf5ae70e5befbbd"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.197%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.09448. Missing scores are unknown.","source_id":"sr-1136a1bde8530a4f810aedbcf9196ec5"}],"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-007059983e5e0c9edbb3066f00e88379","url":"https://github.com/advisories/GHSA-v753-g4cw-jm48","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-v753-g4cw-jm48","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:08.420Z"},{"id":"sr-1c20295bbf928148ccf5ae70e5befbbd","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118656","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-118656","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-03T09:59:16.598Z"},{"id":"sr-1136a1bde8530a4f810aedbcf9196ec5","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-2026-118656","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.375Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-007059983e5e0c9edbb3066f00e88379"],"technology":"github.com/labstack/echo/v5","known_exclusions":[],"conditions_summary":"## Summary\n\nEcho'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.\n\nBrowsers 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` value of ``/\\t/attacker.example`` is therefore resolved by the browser as an absolute URL on `attacker.example`. Confirmed end to end in a headless browser.\n\n## Technical background\n\n### The guard\n\n`middleware/slash.go:144` (duplicated verbatim at `echo.go:958`):\n\n```go\nfunc sanitizeURI(uri string) string {\n\t// double slash `\\\\`, `//` or even `\\/` is absolute uri for browsers and by redirecting request to that uri\n\t// we are vulnerable to open redirect attack. so replace all slashes from the beginning with single slash\n\tif len(uri) > 1 && (uri[0] == '\\\\' || uri[0] == '/') && (uri[1] == '\\\\' || uri[1] == '/') {\n\t\turi = \"/\" + strings.TrimLeft(uri, `/\\`)\n\t}\n\treturn uri\n}\n`","public_affected_ranges":["< 5.4.0"]},{"certainty":"source_listed","source_ids":["sr-007059983e5e0c9edbb3066f00e88379"],"technology":"github.com/labstack/echo/v4","known_exclusions":[],"conditions_summary":"## Summary\n\nEcho'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.\n\nBrowsers 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` value of ``/\\t/attacker.example`` is therefore resolved by the browser as an absolute URL on `attacker.example`. Confirmed end to end in a headless browser.\n\n## Technical background\n\n### The guard\n\n`middleware/slash.go:144` (duplicated verbatim at `echo.go:958`):\n\n```go\nfunc sanitizeURI(uri string) string {\n\t// double slash `\\\\`, `//` or even `\\/` is absolute uri for browsers and by redirecting request to that uri\n\t// we are vulnerable to open redirect attack. so replace all slashes from the beginning with single slash\n\tif len(uri) > 1 && (uri[0] == '\\\\' || uri[0] == '/') && (uri[1] == '\\\\' || uri[1] == '/') {\n\t\turi = \"/\" + strings.TrimLeft(uri, `/\\`)\n\t}\n\treturn uri\n}\n`","public_affected_ranges":["< 4.16.0"]}],"null_published_at":"2026-11-03T10:03:31.376Z","source_updated_at":"2026-10-28T21:04:23.000Z","source_disclosed_at":"2026-10-28T21:04:22.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T21:56:08.420Z"},{"id":"NVI-00008845","kind":"vulnerability","title":"Echo has Open Redirect via Control-Character Prefix Defeating sanitizeURI","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-v753-g4cw-jm48","CVE-2026-118656"],"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-1136a1bde8530a4f810aedbcf9196ec5"],"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":"2026-10-28T21:04:23.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-007059983e5e0c9edbb3066f00e88379"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.197%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.09448. Missing scores are unknown.","source_id":"sr-1136a1bde8530a4f810aedbcf9196ec5"}],"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-007059983e5e0c9edbb3066f00e88379","url":"https://github.com/advisories/GHSA-v753-g4cw-jm48","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-v753-g4cw-jm48","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:08.420Z"},{"id":"sr-1136a1bde8530a4f810aedbcf9196ec5","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-2026-118656","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.375Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-007059983e5e0c9edbb3066f00e88379"],"technology":"github.com/labstack/echo/v5","known_exclusions":[],"conditions_summary":"## Summary\n\nEcho'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.\n\nBrowsers 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` value of ``/\\t/attacker.example`` is therefore resolved by the browser as an absolute URL on `attacker.example`. Confirmed end to end in a headless browser.\n\n## Technical background\n\n### The guard\n\n`middleware/slash.go:144` (duplicated verbatim at `echo.go:958`):\n\n```go\nfunc sanitizeURI(uri string) string {\n\t// double slash `\\\\`, `//` or even `\\/` is absolute uri for browsers and by redirecting request to that uri\n\t// we are vulnerable to open redirect attack. so replace all slashes from the beginning with single slash\n\tif len(uri) > 1 && (uri[0] == '\\\\' || uri[0] == '/') && (uri[1] == '\\\\' || uri[1] == '/') {\n\t\turi = \"/\" + strings.TrimLeft(uri, `/\\`)\n\t}\n\treturn uri\n}\n`","public_affected_ranges":["< 5.4.0"]},{"certainty":"source_listed","source_ids":["sr-007059983e5e0c9edbb3066f00e88379"],"technology":"github.com/labstack/echo/v4","known_exclusions":[],"conditions_summary":"## Summary\n\nEcho'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.\n\nBrowsers 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` value of ``/\\t/attacker.example`` is therefore resolved by the browser as an absolute URL on `attacker.example`. Confirmed end to end in a headless browser.\n\n## Technical background\n\n### The guard\n\n`middleware/slash.go:144` (duplicated verbatim at `echo.go:958`):\n\n```go\nfunc sanitizeURI(uri string) string {\n\t// double slash `\\\\`, `//` or even `\\/` is absolute uri for browsers and by redirecting request to that uri\n\t// we are vulnerable to open redirect attack. so replace all slashes from the beginning with single slash\n\tif len(uri) > 1 && (uri[0] == '\\\\' || uri[0] == '/') && (uri[1] == '\\\\' || uri[1] == '/') {\n\t\turi = \"/\" + strings.TrimLeft(uri, `/\\`)\n\t}\n\treturn uri\n}\n`","public_affected_ranges":["< 4.16.0"]}],"null_published_at":"2026-10-31T22:13:48.407Z","source_updated_at":"2026-10-28T21:04:23.000Z","source_disclosed_at":"2026-10-28T21:04:22.000Z","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":"2026-10-31T21:56:08.420Z"}],"next_cursor":null,"snapshot_revision":"42594"}