Summary
Deskin through version 3.3.4.3 contains a missing-authentication flaw in its root-owned macOS installer XPC service. A local unprivileged attacker may connect without authentication and cause an attacker-controlled installer package to run with root privileges, potentially compromising the host.
Deskin through version 3.3.4.3 contains a missing-authentication flaw in its root-owned macOS installer XPC service. A local unprivileged attacker may connect without authentication and cause an attacker-controlled installer package to run with root privileges, potentially compromising the host.
Affected context
The vulnerability occurs in the com.deskin.service.installer XPC service when it is exposed to local clients without adequately authenticating or authorizing callers. Risk is present where the service accepts installer requests from unprivileged processes and performs those operations with root privileges.
The vulnerability occurs in the com.deskin.service.installer XPC service when it is exposed to local clients without adequately authenticating or authorizing callers. Risk is present where the service accepts installer requests from unprivileged processes and performs those operations with root privileges.
Exploit preconditions
- Attack surface: A locally accessible macOS XPC service
- Required access: An unprivileged account or process on the affected host
- Trigger point: Invocation of the privileged installer operation
- Why exploitation is possible: The root-owned service does not adequately authenticate or authorize the requesting client before processing installer requests
- Attack surface: A locally accessible macOS XPC service
- Required access: An unprivileged account or process on the affected host
- Trigger point: Invocation of the privileged installer operation
- Why exploitation is possible: The root-owned service does not adequately authenticate or authorize the requesting client before processing installer requests
Why this happens
The underlying issue is a missing authentication and authorization check on a privileged interprocess communication endpoint. A root-owned service trusts local callers without establishing that they are permitted to request installation activity, mapping to CWE-306: Missing Authentication for Critical Function. Because the requested operation executes with elevated privileges, insufficient caller validation turns an exposed service method into a local privilege-escalation path.
The underlying issue is a missing authentication and authorization check on a privileged interprocess communication endpoint. A root-owned service trusts local callers without establishing that they are permitted to request installation activity, mapping to CWE-306: Missing Authentication for Critical Function. Because the requested operation executes with elevated privileges, insufficient caller validation turns an exposed service method into a local privilege-escalation path.
Potential impact
- An attacker may execute arbitrary installer-controlled code with root privileges
- The macOS host could be fully compromised
- System files, security settings, or user data could be modified
- Persistence or additional local accounts could be established
- The vulnerability could enable follow-on attacks against connected services or data
- An attacker may execute arbitrary installer-controlled code with root privileges
- The macOS host could be fully compromised
- System files, security settings, or user data could be modified
- Persistence or additional local accounts could be established
- The vulnerability could enable follow-on attacks against connected services or data
General mitigation guidance
Mitigation generally focuses on enforcing strong identity and authorization boundaries around privileged XPC services.
Common defensive patterns include:
- Requiring authenticated, authorized clients before performing installation operations
- Restricting privileged methods to explicitly approved callers and signed components
- Separating package validation from privileged installation execution
- Validating package provenance, integrity, and intended installation scope
- Applying least privilege to helper services and minimizing root-owned functionality
- Denying access by default and recording rejected or unusual client requests
Mitigation generally focuses on enforcing strong identity and authorization boundaries around privileged XPC services.
Common defensive patterns include:
- Requiring authenticated, authorized clients before performing installation operations
- Restricting privileged methods to explicitly approved callers and signed components
- Separating package validation from privileged installation execution
- Validating package provenance, integrity, and intended installation scope
- Applying least privilege to helper services and minimizing root-owned functionality
- Denying access by default and recording rejected or unusual client requests
How teams detect issues like this
Organizations can assess this weakness through:
- Static analysis and code review of XPC listener configuration and exported methods
- Checks for privileged services that lack caller identity or entitlement validation
- Review of authorization decisions made before root-level installation actions
- Endpoint monitoring for unexpected installer activity initiated by unprivileged processes
- Policy enforcement requiring authentication, signing, and least privilege for privileged IPC services
- Automated security review tools that flag unauthenticated access to critical functions
Organizations can assess this weakness through:
- Static analysis and code review of XPC listener configuration and exported methods
- Checks for privileged services that lack caller identity or entitlement validation
- Review of authorization decisions made before root-level installation actions
- Endpoint monitoring for unexpected installer activity initiated by unprivileged processes
- Policy enforcement requiring authentication, signing, and least privilege for privileged IPC services
- Automated security review tools that flag unauthenticated access to critical functions
Sources
| Source | Link |
|---|---|
| deskin. | deskin.io/ |
| github. | github.com/ |
| vulncheck. | vulncheck.com/ |
