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Use After Free

CVE-2021-43826

Severity High
Score 7.5/10

Summary

Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions of Envoy a crash occurs when configured for :ref:`upstream tunneling <envoy_v3_api_field_extensions.filters.network.tcp_proxy.v3.TcpProxy.tunneling_config>` and the downstream connection disconnects while the the upstream connection or http/2 stream is still being established. There are no workarounds for this issue. Users are advised to upgrade.

  • LOW
  • NETWORK
  • NONE
  • UNCHANGED
  • NONE
  • NONE
  • NONE
  • 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