CVE-2026-30405: GoBGP Denial of Service via NEXT_HOP Path Attribute

github.com/osrg/gobgp/v4 Updated 18 Mar 2026

Summary

16/03/2026
No i
High
7.5

CVE-2026-30405: GoBGP vulnerable to a denial of service via the NEXT_HOP path attribute. Affects github.com/osrg/gobgp/v4 versions < 4.3.0. No fix is published. How to fix ↓

Also tracked for

The same CVE-2026-30405 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.

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Background

GoBGP is an open-source implementation of the Border Gateway Protocol (BGP) written in Go. It is designed to facilitate the exchange of routing information between different networks. GoBGP is widely used in various networking applications due to its flexibility and performance. However, a vulnerability has been identified in version 4.2.0 that allows remote attackers to exploit the NEXT_HOP path attribute, potentially leading to a denial of service.

Vulnerability Detail

The vulnerability in GoBGP arises from improper handling of the NEXT_HOP path attribute, which can be manipulated by a remote attacker. This manipulation can lead to a denial of service, causing the affected system to become unresponsive or crash. The issue is particularly concerning as it can be exploited without authentication, making it accessible to any remote attacker. The vulnerability has been assigned a CVSS score of 7.5, indicating a high severity level.

How To Fix

No fixed version is published for this vulnerability.

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Workaround

As a temporary workaround, you can restrict access to the GoBGP service by implementing firewall rules that limit incoming connections to trusted IP addresses. This will help mitigate the risk of exploitation until the package can be updated.

Conclusion

In summary, CVE-2026-30405 is a significant vulnerability in GoBGP that can lead to denial of service through the NEXT_HOP path attribute. Users are advised to update to version 4.3.0 or later to mitigate this risk. Additionally, utilizing tools like Vulert can enhance your ability to monitor and respond to vulnerabilities in your applications.

See every vulnerability recorded for github.com/osrg/gobgp/v4 →

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FAQ

The impact of this vulnerability is a potential denial of service, which can cause the GoBGP service to crash or become unresponsive.

You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without requiring any signup.

Yes, a patch is available in version 4.3.0 of GoBGP. It is recommended to update to this version or later.

The CVSS score of this vulnerability is 7.5, indicating a high severity level.

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Related vulnerabilities

Recent vulnerabilities recorded for github.com/osrg/gobgp/v4.

How To Fix

No fixed version is published for this vulnerability.

Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →

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