CVE-2025-9230: Out-of-bounds read & write in RFC 3211 KEK Unwrap
Issue summary: An application trying to decrypt CMS messages encrypted using password based encryption can trigger an out-of-bounds read and write.
Impact summary: This out-of-bounds read may trigger a crash which leads to Denial of Service for an application. The out-of-bounds write can cause a memory corruption which can have various consequences including a Denial of Service or Execution of attacker-supplied code.
Although the consequences of a successful exploit of this vulnerability could be severe, the probability that the attacker would be able to perform it is low. Besides, password based (PWRI) encryption support in CMS messages is very rarely used. For that reason the issue was assessed as Moderate severity according to our Security Policy.
The FIPS modules in 3.5, 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue, as the CMS implementation is outside the OpenSSL FIPS module boundary.
Other sources
Out-of-bounds read & write in RFC 3211 KEK Unwrap
— Microsoft
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2025-9230?
CVE-2025-9230 has a high severity rating due to its potential to cause Denial of Service through an out-of-bounds read.
How do I fix CVE-2025-9230?
To fix CVE-2025-9230, you should update to the latest version of OpenSSL that addresses this vulnerability.
What software is affected by CVE-2025-9230?
CVE-2025-9230 affects the OpenSSL library, particularly versions that utilize password-based encryption for CMS messages.
What are the implications of CVE-2025-9230?
The implications of CVE-2025-9230 include potential application crashes and denial of service due to an out-of-bounds read and write.
When was CVE-2025-9230 reported?
CVE-2025-9230 was reported in September 2025, prompting immediate attention for affected users.