CVE-2025-43400 is a medium-severity vulnerability affecting Apple products, including macOS, iOS, iPadOS, and visionOS. This vulnerability allows an out-of-bounds write issue that can be triggered by processing a maliciously crafted font. The vulnerability is particularly concerning as it could lead to unexpected termination of the application or corrupt process memory, which poses a significant risk to users.
The CVSS score for this vulnerability is 6.3, indicating a medium level of severity, which should prompt organizations to take action. The attack vector for this vulnerability is network-based, meaning that an attacker could exploit it remotely, increasing the urgency for defenders to address it. Organizations should prioritize patching immediately.
As of the latest information, there is confirmed exploit availability. This adds to the urgency for organizations to take proactive measures to secure their systems from potential exploitation. Continuous monitoring and timely updates are critical in mitigating the risks associated with this vulnerability.
Organizations utilizing affected Apple products need to remain vigilant, especially given the potential for exploitation and the nature of the vulnerability. It is essential to stay informed about future updates and vulnerability disclosures to ensure robust security posture.
Vulnerability Details
According to Apple, this vulnerability allows an out-of-bounds write issue that has been addressed with improved bounds checking. The issue is fixed in watchOS 26.1 and tvOS 26.1. This vulnerability is classified under CWE-787.
The CVSS vector for this vulnerability is CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L, indicating low attack complexity, no privileges required, and user interaction is necessary.
The vulnerability affects the following products: iPadOS, iPhone OS, macOS, and visionOS. The publication date of this vulnerability is September 29, 2025.
Technical Analysis
The root cause of CVE-2025-43400 is an out-of-bounds write vulnerability. This typically occurs when a program writes data outside the boundaries of allocated memory, which can corrupt data or cause unexpected behavior.
The attack vector is network-based, meaning that an attacker can exploit the vulnerability remotely, possibly by sending a specially crafted font file to an unsuspecting victim. The attack complexity is low, as no special conditions are required for exploitation. The attacker does not require any privileges, but user interaction is necessary to trigger the vulnerability. This could involve the user opening a malicious document or visiting a compromised webpage.
The potential impacts include low confidentiality, integrity, and availability. Successful exploitation could lead to application termination or memory corruption.
Risk & Impact Analysis
Risk to organizations includes the potential for unexpected application crashes and exposure of sensitive data due to memory corruption. Given the medium CVSS score, organizations should assess their environment for exposure to this vulnerability, particularly in applications that process font files.
The blast radius for this vulnerability could be significant if exploited in high-traffic environments where malicious fonts are processed frequently. Organizations should prioritize patching immediately to mitigate this risk.
The urgency of response is underscored by the exploit availability. As this vulnerability is actively being exploited, swift remediation actions are necessary to prevent potential breaches.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | Yes |
Public PoC | Yes |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The vulnerability affects the following versions of Apple products: iPadOS versions prior to 26.1, iPhone OS versions prior to 26.1, macOS versions 14.0 to 14.8.1, 15.0 to 15.7.1, and all versions of visionOS prior to 26.0.1.
Mitigation & Remediation
Organizations should upgrade to the latest version of affected Apple products. Specifically, ensure to update to watchOS 26.1, tvOS 26.1, or newer versions of macOS, iPadOS, and iPhone OS to mitigate this vulnerability.
For environments where an immediate upgrade is not possible, consider implementing strict network controls to limit exposure to potentially malicious font files. Regularly monitor application behavior for anomalies that may signal exploitation attempts.
Continuous penetration testing
Detection Guidance
Monitoring for this vulnerability should include logging indicators of application crashes, especially those involving font processing. Organizations should also look for behavioral anomalies in applications that could suggest exploitation attempts.
Network signatures can be established to detect malicious font files being transmitted to systems. Additionally, maintain logs of system changes that may correlate with unexpected application behavior.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2025-43400 lies in its demonstration of the risks associated with processing untrusted data. Security teams are encouraged to adopt practices that include rigorous input validation and bounds checking to prevent similar vulnerabilities.
This vulnerability represents a trend of increasing complexity in application vulnerabilities, often arising from improper handling of user input or untrusted data. Organizations should learn from this incident to bolster defenses against such vulnerabilities.
Security teams should prioritize training on secure coding practices and implement regular security assessments to uncover vulnerabilities before they can be exploited.
Penetration testing methodology
In conclusion, organizations should remain vigilant about vulnerabilities such as CVE-2025-43400, ensuring that security measures are in place to prevent exploitation and maintain trust in their systems.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)