tabby: Incorrect Default Permissions
CVE-2024-55950 is a high-severity incorrect default permissions vulnerability in tabby from Eugeny, with a CVSS 4.0 base score of 8.6 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. Affected tabby versions: < 1.0.216. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.31% 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 tabby 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.
Affected products and versions
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- HighSerious loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).
Official description
Tabby (formerly Terminus) is a highly configurable terminal emulator. Prior to 1.0.216, Tabby terminal emulator contains overly permissive entitlements that are unnecessary for its core functionality and plugin system, creating potential security vulnerabilities. The application currently holds powerful permissions including camera, microphone access, and the ability to access personal folders (Downloads, Documents, etc.) through Apple Events, while also maintaining dangerous entitlements that enable code injection. The concerning entitlements are com.apple.security.cs.allow-dyld-environment-variables and com.apple.security.cs.disable-library-validation. Since Tabby's plugins and themes are NodeJS-based without native libraries or frameworks, and no environment variables are used in the codebase, it is recommended to review and remove at least one of the entitlements (com.apple.security.cs.disable-library-validation or com.apple.security.cs.allow-dyld-environment-variables) to prevent DYLD_INSERT_LIBRARIES injection while maintaining full application functionality. This vulnerability is fixed in 1.0.216.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Default Permissions
During installation, installed file permissions are set to allow anyone to modify those files.
How developers prevent this class of flaw
- The architecture needs to access and modification attributes for files to only those users who actually require those actions.
- Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
More Incorrect Default Permissions vulnerabilities (CWE-276)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in tabby
- 8.1 High severity
- 7.8 High severity
- 7.8 High severity
- 7.1 High severity
- 7.0 High severity
- 8.8 High severity
Recent Incorrect Default Permissions vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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