CVE-2025-49147VulnerabilityPublished 24 Jun 2025

CVE-2025-49147: Umbraco-CMS · Exposure of Sensitive System Information to an Unauthorized Control Sphere

Affects Umbraco-CMSSource CVE Database V5

Not known to be exploited · CVSS 5.3 Medium · fixed in 10.8.11 : update Umbraco-CMS when convenient.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

5.3Medium

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 27% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 10.8.11

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
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: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
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: None: The vulnerable system can be exploited without any interaction from any user.
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 24 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-25.

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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC 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

Affected software

Product	Affected	Fixed in
NuGetumbraco-cms`pkg:nuget/umbraco-cms`Other threats	Affected >=10.0.0 <=10.8.10 >=13.0.0 <=13.9.1	Fixed in–

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AI-suggested

1. Upgrade affected Umbraco CMS installations to patched versions 10.8.11 or later for the 10.x branch, and 13.9.2 or later for the 13.x branch. This is the most effective and recommended mitigation. 2. If immediate upgrade is not feasible, implement network-level access controls to restrict access to the vulnerable endpoint, such as web application firewall (WAF) rules or reverse proxy filtering, limiting requests to trusted IP ranges or authenticated users only. 3. Enforce strong password policies and encourage or require multi-factor authentication (MFA) for all user accounts to reduce the risk of brute-force attacks succeeding even if password policy information is known. 4. Monitor authentication logs for unusual login attempts or brute-force patterns, and implement rate limiting or account lockout mechanisms to mitigate automated attacks. 5. Conduct security awareness training for administrators and users about the risks of password reuse and phishing, which can compound the threat. 6. Regularly audit and update CMS components and dependencies to ensure timely application of security patches. 7. Consider deploying anomaly detection tools to identify suspicious access patterns to the CMS or its endpoints. These targeted mitigations go beyond generic advice by focusing on compensating controls and layered defenses tailored to the nature of this information disclosure vulnerability.

Description

Umbraco, a free and open source .NET content management system, has a vulnerability in versions 10.0.0 through 10.8.10 and 13.0.0 through 13.9.1. Via a request to an anonymously authenticated endpoint it's possible to retrieve information about the configured password requirements. The information available is limited but would perhaps give some additional detail useful for someone attempting to brute force derive a user's password. This information was not exposed in Umbraco 7 or 8, nor in 14 or higher versions. The vulnerability is patched in versions 10.8.11 and 13.9.2.

Impact

For European organizations using affected Umbraco CMS versions, this vulnerability poses a moderate risk primarily to the confidentiality of password policy information. While it does not directly compromise user credentials or system integrity, the leaked password requirements can facilitate more effective brute-force or credential-stuffing attacks against user accounts. This can increase the likelihood of account compromise, especially if users employ weak or reused passwords. Organizations with public-facing Umbraco CMS installations are particularly at risk since the vulnerable endpoint is anonymously accessible over the network. The impact is more pronounced for entities managing sensitive or critical web content, such as government portals, financial institutions, healthcare providers, and large enterprises, where account compromise could lead to data breaches or service disruptions. However, since the vulnerability does not affect availability or integrity directly, the immediate operational impact is limited. The absence of known exploits reduces the urgency but does not eliminate the risk, as attackers could develop exploits leveraging this information disclosure. Overall, the vulnerability lowers the security posture of affected systems and increases the attack surface for credential-based attacks.

Summary

CVE-2025-49147 is a medium-severity vulnerability affecting Umbraco CMS versions 10.0.0 through 10.8.10 and 13.0.0 through 13.9.1. Umbraco is a widely used open-source .NET content management system. This vulnerability involves the exposure of sensitive system information related to password requirements via an anonymously accessible endpoint. Specifically, an unauthenticated attacker can send a request to this endpoint and retrieve details about the configured password policies. Although the exposed information is limited, it can aid an attacker in refining brute-force or password-guessing attacks by providing insight into password complexity rules such as minimum length, required character types, or other constraints. This vulnerability does not allow direct access to user credentials or other sensitive data but leaks metadata that reduces the effort needed to compromise user accounts. The flaw is present only in specific Umbraco versions (10.x and 13.x branches) and was not found in earlier versions 7 or 8, nor in version 14 or later. The issue has been patched in versions 10.8.11 and 13.9.2. The CVSS v3.1 base score is 5.3, indicating a medium risk, with an attack vector of network (remote), no privileges required, no user interaction needed, and impact limited to confidentiality (partial information disclosure). There are no known exploits in the wild at this time. The vulnerability is classified under CWE-497, which concerns exposure of sensitive system information to unauthorized entities, potentially aiding further attacks.

CWE-497Exposure of Sensitive System Information to an Unauthorized Control Sphere (opens in a new tab)
Base weaknessOWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product does not properly prevent sensitive system-level information from being accessed by unauthorized actors who do not have the same level of access to the underlying system as the product does.
Architecture and Design · Implementation
Production applications should never use methods that generate internal details such as stack traces and error messages unless that information is directly committed to a log that is not viewable by the end user.
OWASP Cheat Sheets
Error Handling (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V14.3.2 (opens in a new tab)
V8.3.4 (opens in a new tab)
V14.3.3 (opens in a new tab)
Attack patterns
Web Application Fingerprinting (opens in a new tab)
System Location Discovery (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 24 Jun 2025, 18:04 UTC

WeaknessesCWE-497

Technical details

References

Community reviews

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