Security readout for executives and security teams
Plain-English summary
CVE-2021-39806 is an Android 12L local privilege escalation issue caused by memory corruption. The public record says exploitation requires triggering an initialization failure during servicemanager startup, with no user interaction and no additional execution privileges needed.
Executive priority
Treat this as a targeted Android fleet hygiene issue, not a confirmed internet-scale emergency. Prioritize patch verification for Android 12L devices because the impact is local privilege escalation without user interaction.
Technical view
The flaw is a double free in closef of label_backends_android.c. If an attacker can trigger an initialization failure during servicemanager startup, memory corruption may allow local escalation of privilege. The source bundle names Android 12L and Android ID A-215387420.
Likely exposure
Exposure is limited to Android 12L according to the provided CVE data. The bundle does not identify specific device models, build numbers, or downstream vendor variants beyond the Android and Pixel bulletin reference.
Exploitation context
The source bundle does not report active exploitation, and KEV status is false. Exploitation is described as local and dependent on triggering an initialization failure during servicemanager startup; no user interaction is required.
Researcher notes
Evidence is sparse: no CVSS, CWE, exploit status, or detailed patch text is provided in the bundle. Analysis should stay anchored to the Android 12L affected product, double-free root cause, and servicemanager startup failure condition.
Mitigation direction
- Check Android and device vendor guidance for CVE-2021-39806 applicability.
- Apply the relevant vendor security update for affected Android 12L devices.
- Prioritize devices without June 2022 security bulletin coverage or equivalent vendor fixes.
- Restrict untrusted local app execution where device update status is uncertain.
Validation and detection
- Inventory devices running Android 12L.
- Verify each device security patch level against vendor guidance for CVE-2021-39806.
- Confirm affected fleets received applicable June 2022 Android or Pixel bulletin fixes.
- Track exceptions where vendor guidance is unavailable or devices cannot be updated.
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-2021-39806 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/pixel/2022-06-01CVE 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.