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Use After Free

CVE-2022-48872

Severity High
Score 7/10

Summary

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix use-after-free race condition for maps It is possible that in between calling fastrpc_map_get() until map->fl->lock is taken in fastrpc_free_map(), another thread can call fastrpc_map_lookup() and get a reference to a map that is about to be deleted. Rewrite fastrpc_map_get() to only increase the reference count of a map if it's non-zero. Propagate this to callers so they can know if a map is about to be deleted. Fixes this warning: refcount_t: addition on 0; use-after-free. WARNING: CPU: 5 PID: 10100 at lib/refcount.c:25 refcount_warn_saturate ... Call trace: refcount_warn_saturate [fastrpc_map_get inlined] [fastrpc_map_lookup inlined] fastrpc_map_create fastrpc_internal_invoke fastrpc_device_ioctl __arm64_sys_ioctl invoke_syscall

  • HIGH
  • LOCAL
  • HIGH
  • UNCHANGED
  • NONE
  • LOW
  • HIGH
  • HIGH

CWE-416 - Use After Free

Use-after-free (UaF) vulnerability occurs when the application is using a pointer to memory that has been freed. Any attempt to read/write to a buffer after it is de-allocated allows memory corruption, sensitive information exposure, and can potentially lead to arbitrary code execution.

References

Advisory Timeline

  • Published