Answer in brief
CVE-2026-118262 records a High severity (CVSS 8.2) vulnerability in Echo: WebSocket proxy can retain connections and handlers after client disconnect. The current sources do not mark it as known exploited. The current feed maps labstack/echo (generic), github.com/labstack/echo/v4 (go), github.com/labstack/echo/v4 (go), github.com/labstack/echo/v5 (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.2. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps labstack/echo (generic), github.com/labstack/echo/v4 (go), github.com/labstack/echo/v4 (go), github.com/labstack/echo/v5 (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| labstack/echogeneric | >=4.15.0 <4.16.1 || >=5.0.0 <5.4.1 | 4.16.1, 5.4.1 |
| github.com/labstack/echo/v4go | >=4.15.0,<4.16.1 | 4.16.1 |
| github.com/labstack/echo/v4go | >=4.15.0 <4.16.1 | 4.16.1 |
| github.com/labstack/echo/v5go | >=5.0.0,<5.4.1 | 5.4.1 |
| github.com/labstack/echo/v5go | >=5.0.0 <5.4.1 | 5.4.1 |
Published upstream
Oct 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 23, 2026
Echo is a Go web framework. From 4.15.0 until 4.16.1 and 5.4.1, Echo's Proxy middleware can retain a handler, copy goroutines, and network connections after a WebSocket client disconnects when the upstream keeps its connection open. The raw proxy waits for both copy directions without reliably closing the peer connection when one direction ends, including when a rejected upgrade response uses HTTP keep-alive. Repeated connections can accumulate resources and cause denial of service, depending on proxy-route accessibility, upstream behavior, and connection deadlines. This issue is fixed in 4.16.1 and 5.4.1.
Quoted source text, attributed separately from HOL analysis.