CVE-2026-20422

7.5 HIGH
Denial of Service

📋 TL;DR

This vulnerability in MediaTek modems allows remote denial of service through improper input validation. An attacker can crash the system by connecting a device to a rogue base station without requiring user interaction. This affects devices using vulnerable MediaTek modem chipsets.

💻 Affected Systems

Products:
  • MediaTek modem chipsets
Versions: Specific versions not detailed in CVE; affected versions prior to patch MOLY00827332
Operating Systems: Android and other OS using MediaTek modems
Default Config Vulnerable: ⚠️ Yes
Notes: Affects devices with vulnerable MediaTek modem firmware; exact device models not specified in CVE.

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete system crash requiring device reboot, potentially disrupting critical communications and services on affected mobile devices.

🟠

Likely Case

Temporary denial of service causing dropped connections and requiring device restart to restore functionality.

🟢

If Mitigated

No impact if patched or if devices are not exposed to rogue base stations in controlled environments.

🌐 Internet-Facing: HIGH - Attack can be triggered remotely via rogue base stations without authentication.
🏢 Internal Only: MEDIUM - Requires proximity to deploy rogue base station, but no authentication needed once in range.

🎯 Exploit Status

Public PoC: ✅ No
Weaponized: UNKNOWN
Unauthenticated Exploit: ⚠️ Yes
Complexity: MEDIUM

Requires attacker to operate rogue base station within range of target device; no user interaction needed.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Patch ID: MOLY00827332

Vendor Advisory: https://corp.mediatek.com/product-security-bulletin/February-2026

Restart Required: Yes

Instructions:

1. Check device manufacturer for firmware updates. 2. Apply MediaTek modem firmware patch MOLY00827332. 3. Reboot device after patch installation.

🔧 Temporary Workarounds

Disable automatic network selection

all

Prevent devices from automatically connecting to unknown base stations

Use trusted networks only

all

Configure devices to connect only to known, trusted cellular networks

🧯 If You Can't Patch

  • Restrict physical access to prevent rogue base station deployment near critical devices
  • Implement network monitoring for unusual base station connections

🔍 How to Verify

Check if Vulnerable:

Check modem firmware version against MediaTek security bulletin; contact device manufacturer for specific vulnerability status.

Check Version:

Device-specific commands vary by manufacturer; typically in Settings > About Phone > Baseband Version

Verify Fix Applied:

Verify patch MOLY00827332 is applied in modem firmware version information.

📡 Detection & Monitoring

Log Indicators:

  • Unexpected modem resets
  • Base station connection errors
  • System crash logs mentioning modem

Network Indicators:

  • Connections to unknown base station IDs
  • Unusual signal strength patterns

SIEM Query:

Search for modem crash events or base station connection anomalies in device logs

📊 Metadata

CVE ID: CVE-2026-20422
CVSS v3 Score: 7.5 (HIGH)
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-617
Published: February 2, 2026
Last Updated: February 4, 2026

🤖 AI-assisted analysis, reviewed for accuracy

🔗 References

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