CVE-2021-43411: gnu hurd Race Condition

Vulnerability summary

CVE-2021-43411 is a high (CVSS 8.5) Race Condition vulnerability in gnu hurd. EPSS estimates a 1.27% chance of exploitation in the next 30 days, higher than 69.3% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 07-11-2021
   PublishedVulnerability first disclosed.
2. 04-08-2024
   Last modifiedVulnerability information updated.

Description

An issue was discovered in GNU Hurd before 0.9 20210404-9. When trying to exec a setuid executable, there's a window of time when the process already has the new privileges, but still refers to the old task and is accessible through the old process port. This can be exploited to get full root access.

• CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.