SB2026021271 - Ubuntu update for dnsdist

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Resource exhaustion (CVE-ID: CVE-2025-8671)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to application does not properly control consumption of internal resources when handling HTTP/2 requests. A remote attacker can send specially crafted HTTP requests to the affected server and consume its all available memory, leading to denial of service.

2) Resource exhaustion (CVE-ID: CVE-2025-30193)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of incoming TCP connections from the client. A remote attacker can initiate a crafted TCP exchange and perform a denial of service (DoS) attack through stack exhaustion.

3) Resource exhaustion (CVE-ID: CVE-2025-30187)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to application does not properly control consumption of internal resources within the nghttp2 library when handling incoming DNS over HTTPS queries. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

Remediation

Install update from vendor's website.

References

• https://ubuntu.com/security/notices/USN-8037-1