VulnerabilityPublished 31 Mar 2026

CVE-2026-0397: PowerDNS DNSdist · Overly Permissive Cross-domain Whitelist

Affects PowerDNS DNSdistSource CVE Database V5

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Not known to be exploited · CVSS 3.1 Low : upgrade to 2.0.3 or 1.9.12 when convenient.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

3.1Low

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.0.3, 1.9.12

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 31 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade DNSdist and dnsdist to 2.0.3 or 1.9.12.

Affected software

Product	Affected	Fixed in
PowerDNSDNSdist	Affected >=2.0.0 <2.0.3	Fixed in 2.0.3
PowerDNSDNSdist	Affected >=1.9.0 <1.9.12	Fixed in 1.9.12
GitHubdnsdist`pkg:github/dnsdist`Other threats	Affected >=1.9.0 <1.9.12 >=2.0.0 <2.0.3	Fixed in 1.9.12 2.0.3

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

To mitigate CVE-2026-0397, organizations should first verify whether the internal webserver in DNSdist is enabled; if not required, it should remain disabled to eliminate exposure. If the internal webserver is necessary, administrators must review and tighten the CORS policy to restrict allowed origins strictly to trusted domains, avoiding wildcard or overly broad allowances. Implement Content Security Policy (CSP) headers to reduce the risk of malicious script execution. Educate administrators about phishing and social engineering risks to prevent them from visiting untrusted or malicious websites while logged into the dashboard. Regularly update DNSdist to the latest versions where this vulnerability is addressed or patched. Network segmentation and access controls should limit dashboard access to trusted networks and users. Monitoring and logging access to the dashboard can help detect suspicious activity. Finally, consider deploying web application firewalls (WAFs) that can detect and block cross-origin attacks targeting the dashboard interface.

Description

When the internal webserver is enabled (default is disabled), an attacker might be able to trick an administrator logged to the dashboard into visiting a malicious website and extract information about the running configuration from the dashboard. The root cause of the issue is a misconfiguration of the Cross-Origin Resource Sharing (CORS) policy.

Impact

The primary impact of CVE-2026-0397 is the potential unauthorized disclosure of sensitive configuration information from the DNSdist dashboard. Such information could include network topology, DNS routing rules, or other operational details that could aid attackers in further reconnaissance or targeted attacks. Although the vulnerability does not allow modification of data or denial of service, the leakage of configuration data can weaken an organization's security posture. The requirement for user interaction (administrator visiting a malicious site) limits the scope of exploitation but does not eliminate risk, especially in environments where administrators may be targeted via phishing or social engineering. Organizations relying on DNSdist for DNS load balancing or security may face increased risk of information leakage if the internal webserver is enabled with default or weak CORS settings. The impact is thus primarily on confidentiality, with no direct effect on integrity or availability.

CWE-942Permissive Cross-domain Security Policy with Untrusted Domains (opens in a new tab)
Variant weaknessOWASP Top 10 A02:2025: Security Misconfiguration (opens in a new tab)
The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.
Architecture and Design · Operation · Attack Surface Reduction
Define a restrictive Content Security Policy or cross-domain policy file.
Architecture and Design · Operation · Attack Surface Reduction
Avoid using wildcards in the CSP / cross-domain policy file. Any domain matching the wildcard expression will be implicitly trusted, and can perform two-way interaction with the target server.
Architecture and Design · Operation · Environment Hardening
For Flash, modify crossdomain.xml to use meta-policy options such as 'master-only' or 'none' to reduce the possibility of an attacker planting extraneous cross-domain policy files on a server.
OWASP ASVS 4.0.3
V8.3.8 (opens in a new tab)
V1.14.1 (opens in a new tab)
V13.4.2 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-02.html (opens in a new tab)

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 31 Mar 2026, 12:23 UTC

WeaknessesCWE-942

Technical details

References

Community reviews

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