PatchTheCVECVE-2026-81096: ToolUniverse ran caller-supplied Python inside a sandbox that could be escaped, on a server that required no a
CVE-2026-81096 is a critical-severity flaw (CVSS 10.0) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
ToolUniverse ran caller-supplied Python inside a sandbox that could be escaped, on a server that required no authentication. The executor behind the python_code_executor tool, in python_executor_tool.py, inspected the submitted source for a denied list of attribute names and calls but left the attribute-lookup builtins available and did not stop a dunder attribute reached through a string lookup or through a module already permitted, so a caller
Why this priority
- Critical severity
- CISA SSVC: automatable with total technical impact
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 10.0 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.9% (top 42%) |
| CISA exploited list | No |
| Weakness | CWE-94 |
| Published | 2026-08-27 |
| Last modified | 2026-09-23 |
Last updated 2026-09-23 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-81096?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-81096 being exploited?
CVE-2026-81096 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-81096 affect?
CVE-2026-81096 affects affected software. Severity is critical (CVSS 10.0). ToolUniverse ran caller-supplied Python inside a sandbox that could be escaped, on a server that required no authentication. The executor behind the python_code_executor tool, in python_executor_tool.py, inspected the submitted source for a
How urgent is CVE-2026-81096?
Priority 58/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action