7.5
HIGH CVSS 3.1
CVE-2026-52880
Klever-Go: REST API slow-header connection exhaustion via Gin Engine.Run
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.

INFO

Published Date :

Aug. 7, 2026, 11:17 p.m.

Last Modified :

Oct. 24, 2026, 4:10 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-52880 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Klever-io klever-go
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
Solution
Update Klever-Go to version 1.7.18 to fix denial of service vulnerability.
  • Update Klever-Go to version 1.7.18.
  • Configure appropriate timeouts for HTTP server.
  • Limit incoming connections to the REST API.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-52880.

URL Resource
https://github.com/klever-io/klever-go/releases/tag/v1.7.18
https://github.com/klever-io/klever-go/security/advisories/GHSA-w4c6-7r69-w7j9
https://github.com/klever-io/klever-go/security/advisories/GHSA-w4c6-7r69-w7j9
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-52880 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-52880 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-52880 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Translated by [email protected]

    Oct. 24, 2026

    Action Type Old Value New Value
    Changed Translation Title: klever-go de klever-io, Description: Klever-Go es la implementación en Go del protocolo blockchain de Klever. Las versiones desde la 1.7.14 hasta la 1.7.17 son vulnerables a una denegación de servicio que puede ser activada remotamente. Ambas APIs REST se inician con el método de conveniencia Gin Engine.Run, que atiende solicitudes a través del servidor HTTP predeterminado de Go sin ReadHeaderTimeout, ReadTimeout o MaxHeaderBytes configurados. Como resultado, las conexiones entrantes que nunca completan sus encabezados de solicitud se mantienen abiertas indefinidamente. Cuando un oyente REST es accesible más allá de localhost a través del enlace de todas las interfaces documentado o una implementación de publicación de puerto de Docker, un único cliente no autenticado puede abrir muchas conexiones de encabezado lento y mantenerlas abiertas hasta que los descriptores de archivo del servidor se agoten, impidiendo que la API acepte nuevas conexiones. Esto hace que la API REST no esté disponible para clientes legítimos. Este problema está solucionado en la versión 1.7.18. Title: klever-go de klever-io, Description: Klever-Go es la implementación en Go del protocolo blockchain de Klever. Las versiones desde la 1.7.14 hasta la 1.7.17 son vulnerables a una denegación de servicio que puede ser activada remotamente. Ambas APIs REST se inician con el método de conveniencia Gin Engine.Run, que atiende solicitudes a través del servidor HTTP predeterminado de Go sin ReadHeaderTimeout, ReadTimeout o MaxHeaderBytes configurados. Como resultado, las conexiones entrantes que nunca completan sus encabezados de solicitud se mantienen abiertas indefinidamente. Cuando un oyente REST es accesible más allá de localhost a través del enlace de todas las interfaces documentado o una implementación de publicación de puerto de Docker, un único cliente no autenticado puede abrir muchas conexiones de encabezado lento y mantenerlas abiertas hasta que los descriptores de archivo del servidor se agoten, impidiendo que la API acepte nuevas conexiones. Esto hace que la API REST no esté disponible para clientes legítimos. Este problema está solucionado en la versión 1.7.18.
  • CVE Translated by [email protected]

    Oct. 23, 2026

    Action Type Old Value New Value
    Added Translation Title: klever-go de klever-io, Description: Klever-Go es la implementación en Go del protocolo blockchain de Klever. Las versiones desde la 1.7.14 hasta la 1.7.17 son vulnerables a una denegación de servicio que puede ser activada remotamente. Ambas APIs REST se inician con el método de conveniencia Gin Engine.Run, que atiende solicitudes a través del servidor HTTP predeterminado de Go sin ReadHeaderTimeout, ReadTimeout o MaxHeaderBytes configurados. Como resultado, las conexiones entrantes que nunca completan sus encabezados de solicitud se mantienen abiertas indefinidamente. Cuando un oyente REST es accesible más allá de localhost a través del enlace de todas las interfaces documentado o una implementación de publicación de puerto de Docker, un único cliente no autenticado puede abrir muchas conexiones de encabezado lento y mantenerlas abiertas hasta que los descriptores de archivo del servidor se agoten, impidiendo que la API acepte nuevas conexiones. Esto hace que la API REST no esté disponible para clientes legítimos. Este problema está solucionado en la versión 1.7.18.
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 11, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/klever-io/klever-go/security/advisories/GHSA-w4c6-7r69-w7j9
    Added SSVC {'id': 'CVE-2026-52880', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-11T01:21:07.018712Z'}
  • New CVE Received by [email protected]

    Aug. 07, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'klever-io', 'product': 'klever-go', 'versions': [{'status': 'affected', 'version': '>= 1.7.14, < 1.7.18'}]}]
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-400
    Added CWE CWE-770
    Added Reference https://github.com/klever-io/klever-go/releases/tag/v1.7.18
    Added Reference https://github.com/klever-io/klever-go/security/advisories/GHSA-w4c6-7r69-w7j9
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.