CVE-2026-113776 pypa CVE debrief

Who should care

Defenders responsible for managing virtual environments, particularly in environments where user activation of virtual environments is common, should assess exposure and prioritize remediation.

Why it matters

Defenders should care about CVE-2026-113776 because it allows code execution when a user activates a virtual environment with a specially crafted path, potentially leading to unauthorized access or privilege escalation. Affected versions require verification and remediation.

• Code execution upon virtual environment activation
• Potential for unauthorized access or privilege escalation
• Need for verification of affected versions and remediation

Technical summary

The virtualenv activation scripts are vulnerable to code execution when a user activates a virtual environment with a specially crafted path. The vulnerability is due to the way placeholders in activation templates are replaced. This allows code execution upon virtual environment activation and potential for unauthorized access or privilege escalation. Affected versions require verification and remediation. The reporter demonstrated exploitation through various shell scripts, including bash, fish, and Python code execution.

Defensive priority

Defenders should prioritize verifying and remediating affected virtualenv deployments, particularly in environments where user activation of virtual environments is common.

Recommended defensive actions

• Verify virtualenv version and apply patch if necessary
• Restrict write access to virtual environment directories
• Monitor virtual environment activation for suspicious activity
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on a vulnerability in virtualenv activation scripts. The vulnerability allows code execution when a user activates a virtual environment with a specially crafted path. The reporter demonstrated exploitation through various shell scripts.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.