PowerDNS DNSdist up to 1.9.12/2.0.3 memory allocation

Summaryinfo

A vulnerability identified as problematic has been detected in PowerDNS DNSdist up to 1.9.12/2.0.3. This vulnerability affects unknown code. The manipulation leads to memory allocation. This vulnerability is referenced as CVE-2026-33595. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in PowerDNS DNSdist up to 1.9.12/2.0.3. It has been rated as problematic. This issue affects some unknown functionality. The manipulation with an unknown input leads to a memory allocation vulnerability. Using CWE to declare the problem leads to CWE-789. The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. Impacted is availability. The summary by CVE is:

A client can trigger excessive memory allocation by generating a lot of errors responses over a single DoQ and DoH3 connection, as some resources were not properly released until the end of the connection.

The weakness was published by Mehtab Zafar. It is possible to read the advisory at dnsdist.org. The identification of this vulnerability is CVE-2026-33595 since 03/23/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 321078 (Fedora 44 : dnsdist (2026-51cdd1292b)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.9.13 or 2.0.4 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (321078) and EUVD (EUVD-2026-24933). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Domain Name Software

Vendor

• PowerDNS

Name

• DNSdist

Version

• 1.9.0
• 1.9.1
• 1.9.2
• 1.9.3
• 1.9.4
• 1.9.5
• 1.9.6
• 1.9.7
• 1.9.8
• 1.9.9
• 1.9.10
• 1.9.11
• 1.9.12
• 2.0.0
• 2.0.1
• 2.0.2
• 2.0.3

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

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Threat Intelligenceinfo

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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