AndroidOperating system · Google

CVE-2023-33891

MEDIUM · 5.5 CVSS v3.1 Published 2023-07-12
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
57/100
Remediation priority · Elevated
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In telephony service, there is a missing permission check. This could lead to local information disclosure with no additional execution privileges needed.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

This is a local privilege escalation vulnerability in Android's telephony service where a missing permission check allows an application with standard Android permissions to access sensitive telephony information (such as call logs, phone numbers, or SIM details) that should require elevated privileges. The CVSS 5.5 indicates low confidentiality impact but no integrity or availability impact.

MitigationApply the vendor patch for CVE-2023-33891 which adds proper permission validation in the telephony service to enforce access controls. Until patched, monitor app installations for suspicious telephony-related permissions.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
AndroidOperating system
Affected:= 10.0= 11.0= 12.0= 13.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Android OS version
    Go to Settings > About Phone > Android version (or Settings > System > About Phone > Android version on some devices). Record the exact version number displayed.
    Affected if The version is 10.0, 11.0, 12.0, or 13.0 exactly.
  2. Verify the telephony service is accessible
    Attempt to access the TelephonyManager service through ADB by running 'adb shell service list' and look for 'telephony' in the list, or check if any installed application can query telephony information without encountering permission errors.
    Affected if The telephony service is running and standard permission apps can access call logs, phone numbers, or SIM details without elevated privileges.
  3. Check installed applications for telephony permissions
    Review installed applications in Settings > Apps > Permissions > Telephony (or similar) to see which apps have access to call logs, contacts, or SIM information. Identify if any app with standard permissions (not system or root privileges) has these telephony accesses.
    Affected if Non-system applications without elevated privileges have access to telephony data (call logs, phone numbers, SIM details) when they should require higher-level permissions.
  4. Confirm patch status from vendor
    Check for system updates in Settings > System > Software Update (or Settings > About Phone > Software Update). Look for any security patch notes or updates that reference CVE-2023-33891 or the telephony permission fix.
    Affected if The device has not received a security update addressing CVE-2023-33891, or the update history does not include the relevant telephony permission validation fix.

The device is affected if it runs Android 10, 11, 12, or 13 and has not received the vendor security patch for CVE-2023-33891, allowing standard permission apps to access sensitive telephony information.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the vendor patch for CVE-2023-33891 which adds proper permission validation in the telephony service to enforce access controls. Until patched, monitor app installations for suspicious telephony-related permissions.

Fix this in Android Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,560
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-33891 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data