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Fencer Intel
medium 5.3

CVE-2021-22552 json

Memory overread secure enclave in Asylo 0.6.2

published 5y ago modified 4mo ago also EUVD-2021-9693

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits
0
none known

Summary

An untrusted memory read vulnerability in Asylo versions up to 0.6.1 allows an untrusted attacker to pass a syscall number in MessageReader that is then used by sysno() and can bypass validation. This can allow the attacker to read memory from within the secure enclave. We recommend updating to Asylo 0.6.3 or past https://github.com/google/asylo/commit/90d7619e9dd99bcdb6cd28c7649d741d254d9a1a

Patch / fix

Is CVE-2021-22552 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/google/asylo/commit/90d7619e9dd99bcdb6cd28c7649d741d254d9a1a referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N

Affected products

  • Google LLC Asylo

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.