rt: Improper Authentication
CVE-2026-41076 is a high-severity improper authentication vulnerability in rt from Bestpractical, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected rt versions: < 5.0.10; >= 6.0.0, < 6.0.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.39% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of rt you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Bestpractical | rt | < 5.0.10; >= 6.0.0, < 6.0.3 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
RT is an open source, enterprise-grade issue and ticket tracking system. Versions 5.0.9 and prior in addition to 6.0.0 through 6.0.2 contain an authentication bypass vulnerability in RT installations that use LDAP/AD for user authentication. Under certain LDAP server configurations, an attacker may be able to authenticate as any LDAP-backed RT user without supplying valid credentials. This issue has been fixed in versions 5.0.10 and 6.0.3. If developers are unable to upgrade immediately, they can temporarily work around this issue by reviewing their LDAP server's authentication policy to ensure it rejects unauthenticated bind attempts. Upgrading RT remains the recommended fix.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in rt
- 9.1 Critical severity
- 8.8 High severity
- 7.1 High severity
Recent Improper Authentication vulnerabilities
- 9.8 Critical severity
- 7.2 High severity
- 8.8 High severity
- 9.8 Critical severity
- 9.1 Critical severity
- 9.8 Critical severity
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