Security context

What an agent needs to avoid regressing past fixes and find the next vuln in this repo.

saghul/pycares

              master @ 8cf47fa
            

Fixes

CVEs

HIGH

Peak severity

Highlights

Denial of Service: 6 prior fixes. Scrutinize any change in this area.

src/pycares/__init__.py: most-fixed (7 issues). Treat as high-risk during review.

4 high-severity fixes in this history; regressions here are high-impact.

Recurring patterns

The bug types that recur here, drawn from past fixes, not open vulnerabilities.

Use After Free: Concurrent DNS query submissions alongside channel closures can trigger use-after-free conditions on the underlying c-ares channel due to race conditions during garbage collection. This allows attackers to crash the interpreter when pending DNS queries exist.

Denial of Service: Lack of thread-safe synchronization during concurrent operations like channel cancellation and destruction can cause raw handle race conditions, leading to immediate application crashes.

Memory Corruption: Destroying DNS channels while callbacks are still pending can lead to double-free or use-after-free states. Ensuring all pending queries in the c-ares queue are drained before destroying the underlying native object is critical.