Security readout for executives and security teams
Plain-English summary
CVE-2021-39804 is an Android file-picker denial-of-service issue. A crafted HEIF-related file interaction could crash the file picker persistently. It affects Android 11, 12, and 12L. The sources do not indicate data theft, privilege escalation, or code execution.
Executive priority
Treat as a moderate patch-management issue. It can disrupt affected Android users, but the available evidence does not show code execution, privilege escalation, or active exploitation.
Technical view
Android HeifDecoderImpl.cpp reinit can crash because of a missing null check. The CVE describes remote persistent denial of service in the file picker with no additional privileges required, but user interaction is needed.
Likely exposure
Exposure is limited to Android 11, Android 12, and Android 12L devices that have not received the relevant Android April 2022 security bulletin fixes from their vendor or carrier.
Exploitation context
The provided sources do not report active exploitation, and this CVE is not marked KEV. Exploitation requires user interaction and is described as denial of service, not device compromise.
Researcher notes
Evidence is sparse: no CVSS, CWE, commit detail, or exploit reporting is included in the provided bundle. Validate through Android patch-level status and vendor bulletin mapping rather than exploit reproduction.
Mitigation direction
- Apply vendor Android updates covering the April 2022 security bulletin.
- Prioritize managed Android 11, 12, and 12L devices.
- Check OEM and carrier advisories for device-specific patch availability.
- Use MDM compliance policies to flag outdated Android security patch levels.
Validation and detection
- Inventory Android 11, 12, and 12L devices.
- Verify each device security patch level includes April 2022 fixes or later.
- Confirm OEM firmware release notes reference the April 2022 Android bulletin.
- Review support reports for persistent file-picker crashes on Android 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-2021-39804 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.