{"items":[{"id":"NVI-00009056","kind":"vulnerability","title":"Echo: WebSocket proxy can retain connections and handlers after client disconnect","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-9969-6676-49h5","CVE-2026-118262"],"plain_summary":"GitHub lists this reviewed advisory for github.com/labstack/echo/v4, github.com/labstack/echo/v5. 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-94642ec06a988f193322adfc42919f2d"],"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":[],"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-94642ec06a988f193322adfc42919f2d","url":"https://github.com/advisories/GHSA-9969-6676-49h5","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-9969-6676-49h5","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:36.327Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-94642ec06a988f193322adfc42919f2d"],"technology":"github.com/labstack/echo/v4","known_exclusions":[],"conditions_summary":"## Impact\n\nEcho's Proxy middleware could retain a handler, copy goroutines and network connections after a WebSocket client disconnected if the upstream kept its connection open. The raw proxy waited for both copy directions to finish without reliably closing the other connection when one direction ended. Rejected upgrade responses with HTTP keep-alive were one way to trigger this behavior.\n\nRepeated connections can accumulate resources and cause denial of service. The impact depends on the proxy route's accessibility, upstream behavior and configured connection deadlines. This is a medium-severity resource-retention issue; no confidentiality or integrity impact is claimed.\n\n## Affected versions and patch\n\nAffected versions are v4.15.0 through v4.16.0 and v5.0.0 through v5.4.0. The regression was introduced by commit e2133320c7, merged in #2852.\n\nUpgrade to v4.16.1 or v5.4.1. The patch uses Go's HTTP reverse proxy, preserves ordinary HTTP handling for rejected upgrades, and closes both sides of a WebSocket tunnel when either direction ends. It also covers an upstream tha","public_affected_ranges":[">= 4.15.0, < 4.16.1"]},{"certainty":"source_listed","source_ids":["sr-94642ec06a988f193322adfc42919f2d"],"technology":"github.com/labstack/echo/v5","known_exclusions":[],"conditions_summary":"## Impact\n\nEcho's Proxy middleware could retain a handler, copy goroutines and network connections after a WebSocket client disconnected if the upstream kept its connection open. The raw proxy waited for both copy directions to finish without reliably closing the other connection when one direction ended. Rejected upgrade responses with HTTP keep-alive were one way to trigger this behavior.\n\nRepeated connections can accumulate resources and cause denial of service. The impact depends on the proxy route's accessibility, upstream behavior and configured connection deadlines. This is a medium-severity resource-retention issue; no confidentiality or integrity impact is claimed.\n\n## Affected versions and patch\n\nAffected versions are v4.15.0 through v4.16.0 and v5.0.0 through v5.4.0. The regression was introduced by commit e2133320c7, merged in #2852.\n\nUpgrade to v4.16.1 or v5.4.1. The patch uses Go's HTTP reverse proxy, preserves ordinary HTTP handling for rejected upgrades, and closes both sides of a WebSocket tunnel when either direction ends. It also covers an upstream tha","public_affected_ranges":[">= 5.0.0, < 5.4.1"]}],"null_published_at":"2026-10-31T22:13:31.272Z","source_updated_at":"2026-10-28T19:00:21.000Z","source_disclosed_at":"2026-10-23T20:50:17.000Z","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"}