Security readout for executives and security teams
Plain-English summary
CVE-2020-8904 affects Google Asylo versions before 0.6.0. A local, low-privileged attacker could overwrite trusted enclave memory because a pointer range was not validated. The main business concern is disruption or limited tampering of enclave workloads, not data theft based on the CVSS signal.
Executive priority
Treat this as a targeted remediation item for teams using Asylo enclaves, not a broad emergency. Prioritize patching where enclave availability or trusted execution integrity supports critical workloads, because the vulnerability can affect trusted memory and availability.
Technical view
Asylo's ecall_restore function failed to validate the range of the output_len pointer. By manipulating tmp_output_len, an attacker could write to an arbitrary location in trusted enclave memory. The CVSS vector is local, high complexity, low privileges, no user interaction, changed scope, no confidentiality impact, low integrity impact, and high availability impact.
Likely exposure
Exposure is likely limited to environments running Google Asylo stable versions before 0.6.0, especially deployed enclave applications built with the vulnerable code. Organizations not using Asylo or already on 0.6.0 or later are not indicated as affected by the provided sources.
Exploitation context
The CVE is not listed as KEV in the source bundle, and the provided sources do not cite active exploitation. Exploitation requires local access, low privileges, and high attack complexity, reducing broad internet-scale urgency but still mattering for sensitive enclave deployments.
Researcher notes
Evidence maps to CWE-823 and an arbitrary trusted memory overwrite in ecall_restore. The source bundle names the fix version and commit, but does not provide exploit proof, active exploitation evidence, or affected downstream products beyond Google Asylo stable versions before 0.6.0.
Mitigation direction
- Upgrade Google Asylo to version 0.6.0 or later.
- Rebuild affected enclave applications against the patched Asylo version.
- Redeploy rebuilt enclave workloads after normal validation and release checks.
- If upgrade timing is constrained, consult Google Asylo guidance for interim handling.
Validation and detection
- Inventory deployed applications and build artifacts that depend on Google Asylo.
- Confirm all Asylo usage is version 0.6.0 or later.
- Review enclave restore paths for the patched ecall_restore pointer validation behavior.
- Document non-affected systems where Asylo is absent or already patched.
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-2020-8904 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
- 6.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:H
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:C/C:N/I:L/A:H1.14.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.4MediumVector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/google/asylo/commit/e582f36ac49ee11a21d23ad6a30c333092e0a94eCVE reference · x_refsource_CONFIRM
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.