CVE-2020-8904: Arbitrary trusted memory overwrite vulnerability in Asylo

Severity: critical (CVSS 9.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-08-12 · updated 2026-06-17
Weakness: CWE-823

Description

An arbitrary memory overwrite vulnerability in the trusted memory of Asylo exists in versions prior to 0.6.0. As the ecall_restore function fails to validate the range of the output_len pointer, an attacker can manipulate the tmp_output_len value and write to an arbitrary location in the trusted (enclave) memory. We recommend updating Asylo to version 0.6.0 or later.

Affected products

Google LLC Asylo: before 0.6.0 — fixed in 0.6.0

How to fix

Upgrade to a fixed version: Google LLC Asylo 0.6.0. Check the vendor advisory for mitigations.

References

https://github.com/google/asylo/commit/e582f36ac49ee11a21d23ad6a30c333092e0a94e
https://github.com/google/asylo/commit/e582f36ac49ee11a21d23ad6a30c333092e0a94e

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