How to Fix CVE-2026-0021: Android (Bundle Sibling)
By Sai Kiran Pandrala. Last verified: 2026-05-25.
CVE-2026-0021 is a sibling vulnerability in the same vendor advisory as CVE-2026-0005. Apply the same patched build and you close both. The technical detail below is what differs.
| Severity | 8.4 (High) |
|---|---|
| Actively exploited? | No public listing in CISA KEV |
| Affected | Android 16-qpr2; Android 16; Android 15; Android 14 |
| Fixed in | Same patched build as CVE-2026-0005 |
| Type (CWE) | CWE-441 Unintended Proxy or Intermediary ('Confused Deputy') |
What's different about CVE-2026-0021?
In hasInteractAcrossUsersFullPermission of AppInfoBase.java, there is a possible cross-user permission bypass due to a confused deputy. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
How to fix CVE-2026-0021
Apply the patched build per the primary write-up: How to Fix CVE-2026-0005. All commands, verification steps, and rollback notes for Android are listed there.
Frequently asked questions
Does the CVE-2026-0005 patch close CVE-2026-0021?
Yes. Both CVEs are addressed by the same vendor patch. Applying the patched build closes the full bundle.
Is CVE-2026-0021 listed in CISA KEV?
No public KEV listing at the time of this writing.
Where is the official advisory?
See https://source.android.com/docs/security/bulletin/2026/2026-03-01
References
- Official vendor advisory: https://source.android.com/docs/security/bulletin/2026/2026-03-01
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-0021
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Primary: How to Fix CVE-2026-0005
*Written by Sai Kiran Pandrala. Part of the Android bundle. Full procedure at how-to-fix-cve-2026-0005.*