Security readout for executives and security teams
Plain-English summary
CVE-2021-39803 is an Android flaw that could let a remote attacker disclose information after user interaction. The issue is a use-after-free leading to a possible out-of-bounds read. Public sources list Android 10, 11, 12, and 12L as affected.
Executive priority
Treat this as a medium-priority mobile exposure item. It involves possible remote information disclosure, but public evidence provided here does not show active exploitation and user interaction is required. Patch compliance is the main business action.
Technical view
The reported bug is in the destructor path of C2AllocatorIon.cpp, where use-after-free behavior may allow an out-of-bounds read. The CVE description states remote information disclosure is possible without additional execution privileges, but user interaction is required.
Likely exposure
Exposure is likely limited to Android 10, 11, 12, and 12L devices that have not received the relevant Android security bulletin fixes from April 2022 or later OEM updates.
Exploitation context
The provided sources do not report active exploitation, and the CVE is not marked as KEV. Exploitation requires user interaction. The public description does not define the exact trigger path, exposed data, or exploit reliability.
Researcher notes
Public detail is sparse: no CVSS, CWE, proof of concept, affected component behavior, or precise attack vector is included in the bundle. Analysis should stay tied to Android bulletin coverage and device patch status.
Mitigation direction
- Apply Android security updates covering the April 2022 security bulletin or later.
- Confirm OEM firmware includes fixes for CVE-2021-39803.
- Prioritize internet-facing or high-risk mobile fleets with affected Android versions.
- Restrict unsupported Android versions where timely vendor updates are unavailable.
- Monitor vendor advisories for device-specific update guidance.
Validation and detection
- Inventory Android device versions across managed fleets.
- Check device security patch levels against April 2022 or later guidance.
- Verify OEM release notes reference CVE-2021-39803 or the April 2022 bulletin.
- Review mobile management telemetry for unsupported Android 10 through 12L devices.
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.
CVE-2021-39803 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://source.android.com/security/bulletin/2022-04-01CVE 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.