CVE-2025-26780
📋 TL;DR
A missing length check in Samsung Exynos 2400 and Modem 5400 chips allows attackers to cause denial of service via malformed PDCP packets. This affects mobile devices using these specific Samsung processors and modems. The vulnerability impacts cellular network functionality on affected devices.
💻 Affected Systems
- Samsung Exynos 2400 Mobile Processor
- Samsung Modem 5400
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete loss of cellular connectivity on affected devices, rendering them unable to make calls, send texts, or use mobile data.
Likely Case
Temporary disruption of cellular services requiring device reboot to restore functionality.
If Mitigated
Minimal impact if patched; unpatched devices remain vulnerable to targeted attacks.
🎯 Exploit Status
Exploitation requires sending malformed PDCP packets over cellular network; attacker needs proximity or network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Security patch from Samsung (specific version depends on device manufacturer)
Vendor Advisory: https://semiconductor.samsung.com/support/quality-support/product-security-updates/cve-2025-26780/
Restart Required: Yes
Instructions:
1. Check for security updates in device settings. 2. Install available Samsung/device manufacturer security patches. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable cellular data when not needed
androidReduce attack surface by disabling mobile data when Wi-Fi is available
Use Wi-Fi calling when possible
androidRoute calls over Wi-Fi instead of cellular network
🧯 If You Can't Patch
- Limit device use to trusted cellular networks only
- Consider replacing affected devices with patched or different chipset models
🔍 How to Verify
Check if Vulnerable:
Check device specifications for Exynos 2400 or Modem 5400 chipsets and verify security patch level is outdated.Check Version:
Android: Settings > About Phone > Software Information > check Android security patch level and build numberVerify Fix Applied:
Verify latest Samsung/device manufacturer security patch is installed and check patch notes include CVE-2025-26780.📡 Detection & Monitoring
Log Indicators:
- Unexpected modem resets
- PDCP protocol errors in modem logs
- Cellular connection drops
Network Indicators:
- Malformed PDCP packets in cellular traffic
- Unusual packet patterns targeting modem
SIEM Query:
Not applicable - this is a device-level hardware/firmware vulnerability