Klever-Go: REST API slow-header connection exhaustion via Gin Engine.Run (CVE-2026-52880) | HOL Guard CVE

High · CVSS 7.5CVE-2026-52880GHSA-W4C6-7R69-W7J9

Klever-Go: REST API slow-header connection exhaustion via Gin Engine.Run

Answer in brief

CVE-2026-52880 records a High severity (CVSS 7.5) vulnerability in Klever-Go: REST API slow-header connection exhaustion via Gin Engine.Run. The current sources do not mark it as known exploited. The current feed maps klever-io/klever-go (generic), github.com/klever-io/klever-go (go). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 7, 2026Updated Sep 9, 2026Source checked Sep 17, 2026First seen by HOL Jun 11, 2026Material review Sep 9, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. 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.

Affected scope and exposure questions

The current feed maps klever-io/klever-go (generic), github.com/klever-io/klever-go (go). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
klever-io/klever-gogeneric	>= 1.7.14, < 1.7.18	Not reported
github.com/klever-io/klever-gogo	>=1.7.14,<=1.7.17	1.7.18

Recommended response

Check inventory. Check lockfiles and deployed manifests for klever-io/klever-go, github.com/klever-io/klever-go.
Review the reported fix. Update github.com/klever-io/klever-go to 1.7.18 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 9, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jun 11, 2026

Sources and claim methodology

Upstream source description

Klever-Go is the Go implementation of the Klever blockchain protocol. Versions from 1.7.14 through 1.7.17 are vulnerable to a remotely triggerable denial of service. Both REST APIs are started with the Gin Engine.Run convenience method, which serves requests through Go's default HTTP server with no ReadHeaderTimeout, ReadTimeout, or MaxHeaderBytes configured. As a result, incoming connections that never complete their request headers are held open indefinitely. When a REST listener is reachable beyond localhost through the documented all-interface bind or a Docker port-publish deployment, a single unauthenticated client can open many slow-header connections and hold them open until server file descriptors are exhausted, preventing the API from accepting new connections. This renders the REST API unavailable to legitimate clients. This issue is fixed in version 1.7.18.

Quoted source text, attributed separately from HOL analysis.