Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 0.57% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2020
CVE-2020-26253High confidence
.dev domains treated as local in Kirby
getkirby · kirby
Official source article: GitHub GHSA-2CCX-2GF3-8XVV ↗. Check the applicable product and release in the original source.
6.8MediumCVSS 3.1
Scheduled
Patch availableMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Medium, unchanged from published severity.unchanged
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs getkirby kirby and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Patch available01
What, why and how
Kirby is a CMS. In Kirby CMS (getkirby/cms) before version 3.3.6, and Kirby Panel before version 2.5.14 there is a vulnerability in which the admin panel may be accessed if hosted on a .dev domain. In order to protect new installations on public servers that don't have an admin account for the Panel yet, we block account registration there by default. This is a security feature, which we implemented years ago in Kirby 2. It helps to avoid that you forget registering your first admin account on a public server. In this case – without our security block – someone else might theoretically be able to find your site, find out it's running on Kirby, find the Panel and then register the account first. It's an unlikely situation, but it's still a certain risk. To be able to register the first Panel account on a public server, you have to enforce the installer via a config setting. This helps to push all users to the best practice of registering your first Panel account on your local machine and upload it together with the rest of the site. This installation block implementation in Kirby versions before 3.3.6 still assumed that .dev domains are local domains, which is no longer true. In the meantime, those domains became publicly available. This means that our installation block is no longer working as expected if you use a .dev domain for your Kirby site. Additionally the local installation check may also fail if your site is behind a reverse proxy. You are only affected if you use a .dev domain or your site is behind a reverse proxy and you have not yet registered your first Panel account on the public server and someone finds your site and tries to login at `yourdomain.dev/panel` before you register your first account. You are not affected if you have already created one or multiple Panel accounts (no matter if on a .dev domain or behind a reverse proxy). The problem has been patched in Kirby 3.3.6. Please upgrade to this or a later version to fix the vulnerability.
What
Kirby is a CMS. In Kirby CMS (getkirby/cms) before version 3.3.6, and Kirby Panel before version 2.5.14 there is a vulnerability in which the admin panel may be accessed if hosted on a .dev domain. In order to protect new installations on public servers that don't have an admin account for the Panel yet, we block account registration there by default. This is a security feature, which we implemented years ago in Kirby 2. It helps to avoid that you forget registering your first admin account on a public server. In this case – without our security block – someone else might theoretically be able to find your site, find out it's running on Kirby, find the Panel and then register the account first. It's an unlikely situation, but it's still a certain risk. To be able to register the first Panel account on a public server, you have to enforce the installer via a config setting. This helps to push all users to the best practice of registering your first Panel account on your local machine and upload it together with the rest of the site. This installation block implementation in Kirby versions before 3.3.6 still assumed that .dev domains are local domains, which is no longer true. In the meantime, those domains became publicly available. This means that our installation block is no longer working as expected if you use a .dev domain for your Kirby site. Additionally the local installation check may also fail if your site is behind a reverse proxy. You are only affected if you use a .dev domain or your site is behind a reverse proxy and you have not yet registered your first Panel account on the public server and someone finds your site and tries to login at `yourdomain.dev/panel` before you register your first account. You are not affected if you have already created one or multiple Panel accounts (no matter if on a .dev domain or behind a reverse proxy). The problem has been patched in Kirby 3.3.6. Please upgrade to this or a later version to fix the vulnerability.
Why
The product does not properly verify that the source of data or communication is valid.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
Kirby is a CMS. In Kirby CMS (getkirby/cms) before version 3.3.6, and Kirby Panel before version 2.5.14 there is a vulnerability in which the admin panel may be accessed if hosted on a .dev domain. In order to protect new installations on public servers that don't have an admin account for the Panel yet, we block account registration there by default. This is a security feature, which we implemented years ago in Kirby 2. It helps to avoid that you forget registering your first admin account on a public server. In this case – without our security block – someone else might theoretically be able to find your site, find out it's running on Kirby, find the Panel and then register the account first. It's an unlikely situation, but it's still a certain risk. To be able to register the first Panel account on a public server, you have to enforce the installer via a config setting. This helps to push all users to the best practice of registering your first Panel account on your local machine and upload it together with the rest of the site. This installation block implementation in Kirby versions before 3.3.6 still assumed that .dev domains are local domains, which is no longer true. In the meantime, those domains became publicly available. This means that our installation block is no longer working as expected if you use a .dev domain for your Kirby site. Additionally the local installation check may also fail if your site is behind a reverse proxy. You are only affected if you use a .dev domain or your site is behind a reverse proxy and you have not yet registered your first Panel account on the public server and someone finds your site and tries to login at `yourdomain.dev/panel` before you register your first account. You are not affected if you have already created one or multiple Panel accounts (no matter if on a .dev domain or behind a reverse proxy). The problem has been patched in Kirby 3.3.6. Please upgrade to this or a later version to fix the vulnerability.
Why
The product does not properly verify that the source of data or communication is valid.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Origin Validation Error → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- High: exploitation depends on specific conditions
- Security boundary
- Changed: exploitation can affect a different security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-346 ↗
CWE-346: Origin Validation Error. The product does not properly verify that the source of data or communication is valid.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security authority.CNoneConfidentiality impact: No direct loss is represented by this metric.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Affected
- kirby: < 3.3.6
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 8 Dec 2020 · Last source change 4 Aug 2024, 15:56 UTC · CWE-346 · Origin Validation Error
CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2021-0477
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.