Security readout for executives and security teams
Plain-English summary
CVE-2021-22550 affects Google Asylo, a framework for secure enclaves. A local, low-privileged attacker may be able to corrupt or read enclave memory by manipulating pointers inside enclave memory. Business risk depends on whether Asylo enclaves are used in production and what sensitive data they protect.
Executive priority
Treat this as a targeted remediation item, not a broad emergency. Prioritize if Asylo protects sensitive data, keys, or high-value computations. If Asylo is not used, exposure is unlikely based on the provided sources.
Technical view
The issue is a CWE-823 pointer misuse in Asylo UntrustedCacheMalloc::GetBuffer. The CVSS vector is local, high-complexity, low-privilege, no user interaction, with high confidentiality and integrity impact and low availability impact. Sources recommend updating beyond Asylo 0.6.3 or applying commit a47ef55db2337d29de19c50cd29b0deb2871d31c.
Likely exposure
Exposure appears limited to systems building or running Google Asylo enclave applications on vulnerable code. The source bundle does not specify exact affected version ranges beyond recommending versions past 0.6.3 or the named fixing commit.
Exploitation context
The CVE is not listed as KEV in the provided bundle, and no cited source states active exploitation. Exploitation requires local access, low privileges, and high attack complexity, but impact inside the enclave can include serious confidentiality and integrity loss.
Researcher notes
Key gaps are exact affected version boundaries and any exploit maturity beyond the CVE description. Researchers should focus on dependency provenance, enclave build artifacts, and whether vulnerable UntrustedCacheMalloc::GetBuffer code exists in deployed binaries, without assuming broader Google product exposure.
Mitigation direction
- Update Asylo to a version later than 0.6.3.
- Apply or verify commit a47ef55db2337d29de19c50cd29b0deb2871d31c.
- Rebuild and redeploy affected enclave applications after updating Asylo.
- Limit local access to systems hosting sensitive Asylo enclave workloads.
- Monitor Google Asylo guidance for any additional remediation details.
Validation and detection
- Inventory applications and services that depend on Google Asylo.
- Identify the Asylo release or git commit used in each build.
- Confirm deployed builds include the cited fixing commit or a later release.
- Prioritize validation for enclaves handling secrets or integrity-critical processing.
- Review change records to ensure rebuilt enclave binaries were actually deployed.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-823: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-22550 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L15.5Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/google/asylo/commit/a47ef55db2337d29de19c50cd29b0deb2871d31cCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use of Out-of-range Pointer Offset
Use of Out-of-range Pointer Offset represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.