VulnerabilityPublished 31 Mar 2026

CVE-2026-0396: PowerDNS DNSdist · Basic XSS

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 29 Oct 2026, 19:04 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 3% 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:N/I:L/A:N

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: None
Integrity: Low
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: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on 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 29 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-2026-0396, organizations should: 1) Restrict access to the DNSdist web dashboard to trusted administrators only, ideally via network segmentation and VPNs. 2) Disable domain-based dynamic rules (DynBlockRulesGroup:setSuffixMatchRule and setSuffixMatchRuleFFI) if not strictly necessary, as these enable the injection vector. 3) Monitor DNS queries for suspicious patterns that could indicate attempts to inject malicious content. 4) Apply input validation and output encoding on the dashboard interface to neutralize script-related HTML tags, either by updating to patched versions once available or applying vendor-recommended fixes. 5) Educate administrators to avoid clicking on suspicious content within the dashboard and to log out when not actively using the interface. 6) Regularly audit DNSdist configurations and logs for anomalous activity. 7) Follow PowerDNS advisories for updates or patches addressing this vulnerability.

Description

An attacker might be able to inject HTML content into the internal web dashboard by sending crafted DNS queries to a DNSdist instance where domain-based dynamic rules have been enabled via either DynBlockRulesGroup:setSuffixMatchRule or DynBlockRulesGroup:setSuffixMatchRuleFFI.

Impact

The primary impact of CVE-2026-0396 is limited to the integrity of the DNSdist internal web dashboard. An attacker could use this XSS vulnerability to inject malicious HTML or scripts, potentially leading to session hijacking, dashboard manipulation, or misleading display of DNS query data. While confidentiality and availability are not directly affected, the integrity compromise could mislead administrators or enable further attacks if combined with other vulnerabilities. Organizations relying on DNSdist for DNS traffic management and security could face reduced trust in their monitoring tools or risk unauthorized dashboard actions. The requirement for user interaction and the internal nature of the dashboard limit the attack surface, but environments with exposed or widely accessed dashboards are at higher risk. The vulnerability could be leveraged in targeted attacks against DNS infrastructure operators, especially in environments where DNSdist is a critical component of DNS resolution and filtering.

CWE-80Improper Neutralization of Script-Related HTML Tags in a Web Page (opens in a new tab)
Variant weaknessLikelihood of exploit: HighOWASP Top 10 A05:2025: Injection (opens in a new tab)
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.
Implementation
Carefully check each input parameter against a rigorous positive specification (allowlist) defining the specific characters and format allowed. All input should be neutralized, not just parameters that the user is supposed to specify, but all data in the request, including hidden fields, cookies, headers, the URL…
Implementation · Output Encoding
Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8.
Implementation
With Struts, write all data from form beans with the bean's filter attribute set to true.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Injection Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V1.5.1 (opens in a new tab)
V5.3.3 (opens in a new tab)
Attack patterns
XSS Targeting Non-Script Elements (opens in a new tab)
PHP Remote File Inclusion (opens in a new tab)
XSS Through HTTP Query Strings (opens in a new tab)
XSS Through HTTP Headers (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-80

Technical details

References

Community reviews

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