Summary
Brute force exploit can be used to collect valid usernames
Explanation of the vulnerability
It's a brute force exploit that can be used to collect valid usernames by using the “forgot password” function when trying to log into the Backoffice.
If the username/email is known, it is easier to find the corresponding password.
If an email address that was already used and registered by a user, is provided as an input, the server internal processing time takes longer.
If the email address does not exist in the database of the registered users, the server would respond immediately.
Impact
A brute force exploit that can be used to collect valid usernames is possible.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Umbraco.CMS to 8.18.10 or later; Umbraco.CMS to 10.8.1 or later; Umbraco.CMS to 12.3.4 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2023-49278? CVE-2023-49278 is a low-severity security vulnerability in Umbraco.CMS (nuget), affecting versions >= 8.0.0, < 8.18.10. It is fixed in 8.18.10, 10.8.1, 12.3.4.
- Which versions of Umbraco.CMS are affected by CVE-2023-49278? Umbraco.CMS (nuget) versions >= 8.0.0, < 8.18.10 is affected.
- Is there a fix for CVE-2023-49278? Yes. CVE-2023-49278 is fixed in 8.18.10, 10.8.1, 12.3.4. Upgrade to this version or later.
- Is CVE-2023-49278 exploitable, and should I be worried? Whether CVE-2023-49278 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2023-49278 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2023-49278?
- Upgrade
Umbraco.CMSto 8.18.10 or later - Upgrade
Umbraco.CMSto 10.8.1 or later - Upgrade
Umbraco.CMSto 12.3.4 or later
- Upgrade