CVE-2026-118261 Echo: Decompress permits unbounded gzip expansion in v4
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-118261?
CVE-2026-118261 is a high-severity vulnerability in labstack echo, published on 28 Oct 2026.
Official description
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.
Which versions are affected by CVE-2026-118261?
2 open source packages ship an affected version, including github.com/labstack/echo/v4.
| Package | Affected | Fixed in |
|---|---|---|
github.com/labstack/echo/v4 Go | From 4.0.0 | 4.16.1 |
github.com/labstack/echo/v4 Go | From 4.0.0 | 4.16.1 |
How do I fix CVE-2026-118261?
Upgrade github.com/labstack/echo/v4 to 4.16.1 or later.
Is CVE-2026-118261 being exploited?
There is no known exploitation of CVE-2026-118261 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-118261, ECHO-ebd5-7305-625a, GHSA-h7wr-284f-5qvc, ROOT-APP-GOBINARY-GHSA-h7wr-284f-5qvc, UBUNTU-CVE-2026-118261.