CVE-2026-12004: IBM Security Verify Access DoS Vulnerability

CVE-2026-12004 Overview

CVE-2026-12004 is a format string injection vulnerability [CWE-134] affecting IBM Security Verify Access and IBM Verify Identity Access. The flaw resides in the management interface and allows an authenticated attacker with high privileges to trigger denial of service and disclose sensitive information by sending a crafted HTTP request. The vulnerability carries a network attack vector with low complexity and results in a scope change, meaning impact can extend beyond the vulnerable component.

Critical Impact
An authenticated attacker can cause service disruption and leak sensitive process memory contents through a single crafted HTTP request to the management interface.

Affected Products

IBM Security Verify Access 10.0 through 10.0.9.2
IBM Verify Identity Access 11.0 through 11.0.3
IBM Verify Identity Access Container 11.0 through 11.0.3

Discovery Timeline

2026-08-12 - CVE-2026-12004 published to the National Vulnerability Database
2026-08-12 - Last updated in NVD database

Technical Details for CVE-2026-12004

Vulnerability Analysis

The vulnerability is a format string injection [CWE-134] in the management interface of IBM Security Verify Access and IBM Verify Identity Access. Format string flaws occur when attacker-controlled input reaches a formatting function such as printf, sprintf, or syslog as the format specifier argument rather than as data. When exploited, the processing routine interprets specifiers like %s, %x, or %n supplied by the attacker.

A successful attacker can read adjacent memory to disclose sensitive runtime data or write to unintended memory locations to crash the process. The scope change indicated by the CVSS vector means the impact extends beyond the vulnerable component itself, potentially affecting other resources managed by the identity access platform.

Root Cause

The root cause is improper handling of externally supplied input within a format-string-aware function in the management interface. User-controlled data from an HTTP request is passed directly to a formatting routine without sanitization or without using a fixed format specifier, violating safe formatting practices.

Attack Vector

Exploitation requires network access to the management interface and valid high-privilege credentials. The attacker crafts an HTTP request containing format specifiers within a parameter that the server subsequently passes to a vulnerable formatting function. The malformed input produces unintended memory reads or memory corruption that leads to information disclosure or process termination. No user interaction is required to complete the attack.

Refer to the IBM Support Page for vendor technical details on the affected code paths.

Detection Methods for CVE-2026-12004

Indicators of Compromise

HTTP requests to the Verify Access or Verify Identity Access management interface containing format specifier sequences such as %s, %x, %n, or %p within parameters or headers.
Unexpected crashes, restarts, or core dumps of the management interface process.
Authentication events for privileged administrative accounts from unusual source addresses immediately preceding management interface errors.

Detection Strategies

Inspect web server and management interface logs for URI parameters or POST body values containing percent-prefixed format tokens.
Correlate administrative session activity with process error logs to identify malformed requests that trigger faults.
Deploy web application firewall rules that block requests where format specifiers appear in fields expected to contain plain text.

Monitoring Recommendations

Alert on repeated 5xx responses from the management interface following authenticated administrative sessions.
Baseline expected administrative request patterns and flag deviations in payload structure or character composition.
Monitor for privileged credential use outside of maintenance windows and correlate with management interface access.

How to Mitigate CVE-2026-12004

Immediate Actions Required

Apply the fixed versions provided by IBM as documented on the vendor support page.
Restrict network access to the management interface to trusted administrative networks or jump hosts.
Rotate credentials for administrative accounts that had access to the management interface prior to patching.

Patch Information

IBM has published remediation guidance and fixed releases through the IBM Support Page. Upgrade IBM Security Verify Access 10.0.x to a fixed release beyond 10.0.9.2 and IBM Verify Identity Access and Verify Identity Access Container 11.0.x to a fixed release beyond 11.0.3 as specified by IBM.

Workarounds

Place the management interface behind a reverse proxy or web application firewall configured to reject requests containing format string tokens.
Enforce network segmentation so that only designated administrator workstations can reach the management interface.
Reduce the number of accounts assigned high administrative privileges to shrink the exploitable attack surface until patches are applied.

bash

# Example firewall restriction limiting management interface access to an admin subnet
iptables -A INPUT -p tcp --dport 9443 -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9443 -j DROP