Technical impact
The vulnerability stems from libkcapi's improper IV reuse during one‑shot symmetric cipher operations that internally chunk large inputs (over 64 KiB) in stateful modes such as CTR or CBC. Because the same IV is applied to each internal block, encrypted data loses semantic uniqueness and can reveal relationships between plaintexts. This weakens confidentiality and may also jeopardize integrity by producing incorrect cryptographic results.
Affected Systems
The flaw affects Red Hat Enterprise Linux 10, 8, and 9, Red Hat Hardened Images, and Red Hat OpenShift Container Platform 4, all of which include the vulnerable libkcapi library. No specific patch levels or sub‑versions are listed; any deployment using the default library should be considered vulnerable.
Risk and Exploitability
The CVSS score of 6.5 indicates moderate severity. EPSS is not available, so the likelihood of public exploitation is unclear, and the issue is not yet listed in CISA’s KEV catalog. Because a remote attacker can craft a large input for an application that uses libkcapi, the vulnerability can be exploited in a remote or local context if the application accepts user data of sufficient size. The attack does not require elevated privileges in the example description, but the actual success depends on application exposure.
