Citrix App Optimization Listener Service (aotlistenerservice.exe) v25.11.10.8 Crashes Linked to kernelbase.dll

ControlUp’s crash anomaly detection identified an increased rate of crashes affecting the Citrix App Optimization Listener Service, specifically the aotlistenerservice.exe process in version 25.11.10.8. The crashes consistently fault in the kernelbase.dll module, indicating instability within the App Optimization service responsible for session and resource launch enhancements.

This pattern was identified through analysis of anonymized, aggregate crash telemetry across customer environments and suggests a regression affecting this component of the Citrix Workspace platform.

This crash pattern has been observed across more than 220 organizations and is classified as medium severity due to its effect on session and application launch reliability.

Impacted environments may experience:

• Failures when launching published applications or desktops
• Stalled or “zombie” sessions that fail to initialize properly
• Increased delays in resource availability for end users
• Elevated support requests related to Citrix Workspace session reliability

Because the App Optimization Listener Service plays a role in managing session initialization and resource handling, repeated crashes can disrupt user access workflows and degrade overall digital employee experience.

At the time of this finding, no specific update or hotfix has been released by Citrix to address the observed stability issues.

A potential workaround may involve disabling App Optimization features via Citrix policy settings:

Citrix Studio → Policies → App Optimization → Set to “Prohibited”

Disabling App Optimization should prevent AOT features from being initialized, which may reduce exposure to this crash pattern. However, this workaround has not yet been formally validated and should be tested carefully before broad deployment.

Organizations running Citrix Workspace should:

• Monitor crash trends related to aotlistenerservice.exe
• Identify endpoints running version 25.11.10.8
• Track faulting patterns involving kernelbase.dll
• Follow Citrix guidance and release notes for updates addressing Workspace client stability

Where feasible, staged rollouts and controlled testing are recommended until a corrective update becomes available.

This finding suggests a potential stability issue in the current Citrix Workspace release impacting application launch workflows. Recent reports from Citrix users indicate that the crashes may be associated with stalled launches of published resources, and that reinstalling Citrix Workspace or repairing system files does not resolve the behavior.

ControlUp will continue monitoring this crash signature globally and update this finding as new guidance or remediation becomes available. Community observations and testing feedback can help accelerate clarity and resolution.