Answer in brief
CVE-2026-118261 records a High severity (CVSS 8.2) vulnerability in Echo: Decompress permits unbounded gzip expansion in v4. 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). 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). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| labstack/echogeneric | >=4.0.0 <4.16.1 | 4.16.1 |
| github.com/labstack/echo/v4go | >=4.0.0 <4.16.1 | 4.16.1 |
| github.com/labstack/echo/v4go | >=4.0.0,<4.16.1 | 4.16.1 |
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 4.0.0 until 4.16.1, Echo v4's opt-in Decompress middleware exposes a gzip-decoded request stream without limiting its expanded size. A small compressed request can expand into a very large body when a handler reads or binds it, consuming excessive memory or CPU and allowing repeated or concurrent requests to cause denial of service. The middleware is not enabled by default, and limiting only the compressed request size does not bound the decoded size. This issue is fixed in 4.16.1.
Quoted source text, attributed separately from HOL analysis.