CVE-2026-58683: IP Multimedia Subsystem RCE Vulnerability

CVE-2026-58683 Overview

CVE-2026-58683 is an out-of-bounds write vulnerability in the IP Multimedia Subsystem (IMS) component. The flaw stems from improper input validation, classified under [CWE-20]. An attacker can trigger memory corruption remotely without user interaction, leading to remote code execution. Exploitation requires only low privileges and no user interaction over the network. The vulnerability is documented in the Android Security Bulletin for September 2026.

Critical Impact
Attackers can achieve remote code execution on affected devices without user interaction, gaining execution privileges within the IMS component context.

Affected Products

IP Multimedia Subsystem (IMS) component
Android devices referenced in the September 2026 Android Security Bulletin
Pixel devices per the Pixel Update Bulletin, September 2026

Discovery Timeline

2026-09-15 - CVE-2026-58683 published to NVD
2026-09-16 - Last updated in NVD database

Technical Details for CVE-2026-58683

Vulnerability Analysis

The vulnerability resides in the IP Multimedia Subsystem, a framework that delivers IP-based voice, video, and messaging services on mobile networks. Improper input validation allows an attacker to write beyond the bounds of an allocated buffer. This memory corruption primitive can be leveraged to overwrite adjacent memory structures and hijack control flow. Successful exploitation yields remote code execution within the IMS process context without requiring any interaction from the device user.

Root Cause

The root cause is improper input validation [CWE-20] in an IMS message or signaling handler. When the component processes attacker-controlled data, it does not enforce boundary checks on size or content before writing to a fixed-size buffer. This condition permits an out-of-bounds write, corrupting adjacent memory regions used by the parsing routine.

Attack Vector

The attack vector is network-based. An attacker with low privileges can send crafted IMS signaling or media traffic to a vulnerable device. Because IMS handlers process signaling automatically, no user interaction is required to reach the vulnerable code path. Refer to the Android Security Bulletin September 2026 for technical specifics on the affected code paths.

No verified public proof-of-concept code is available. The vulnerability mechanism involves crafted input reaching the IMS parser, bypassing length validation, and writing controlled data past the buffer boundary.

Detection Methods for CVE-2026-58683

Indicators of Compromise

Unexpected IMS process crashes or restarts recorded in device logs
Malformed or oversized SIP/IMS signaling packets targeting mobile endpoints
Anomalous outbound network connections from the IMS process following inbound signaling

Detection Strategies

Monitor telecom signaling infrastructure for malformed SIP, SDP, or IMS control messages that violate protocol length constraints
Correlate IMS component crashes with inbound network traffic patterns to identify probing or exploitation attempts
Baseline normal IMS process behavior on managed mobile fleets to detect anomalous memory or CPU spikes

Monitoring Recommendations

Ingest mobile device logs and carrier signaling telemetry into a centralized SIEM for correlation
Alert on repeated IMS service crashes across multiple devices sharing common network segments
Track patch level compliance across managed Android fleets against the September 2026 bulletin

How to Mitigate CVE-2026-58683

Immediate Actions Required

Apply the September 2026 Android security patch level (2026-09-01 or later) to all affected devices
Inventory managed Android and Pixel devices to confirm current security patch level
Prioritize patching for devices operating on untrusted carrier networks or exposed to hostile signaling environments

Patch Information

Google released fixes in the September 2026 Android Security Bulletin. Device manufacturers and carriers distribute the patch through standard over-the-air updates. Verify remediation by confirming the device reports a security patch level of 2026-09-01 or later. See the Android Security Bulletin September 2026 for the complete list of addressed issues.

Workarounds

Disable IMS-based services such as VoLTE or Wi-Fi Calling on unpatched devices where operationally feasible
Restrict device connectivity to trusted carrier networks until patches are applied
Enforce mobile device management (MDM) policies that block enrollment or network access for devices below the required patch level

bash

# Verify Android security patch level on a managed device
adb shell getprop ro.build.version.security_patch
# Expected output: 2026-09-01 or later