Technical impact
The vulnerability occurs in the BKS/UBER keystore implementation of Bouncy Castle for Java. Prior to version 1.85, an attacker can supply a carefully crafted keystore file whose length fields are not trusted before an integrity check occurs. This allows the library to allocate memory based on an untrusted length, potentially leading to buffer overflows, corruption of internal state, or application crashes. The flaw can disrupt confidentiality, integrity, or availability of the runtime environment if the tampered keystore is processed.
Affected Systems
Affected products are Bouncy Castle Java libraries. For the standard distribution, versions older than 1.85 are vulnerable. For the long‑term support branch, versions older than 2.73.12 are compromised. Systems that embed either distribution and load BKS or UBER keystore files without validating payloads are at risk.
Risk and Exploitability
The CVSS score of 7.1 reflects a high likelihood of successful exploitation in environments where an attacker can inject malicious keystore files. The EPSS score is currently unavailable, and the vulnerability is not listed in the CISA KEV catalog, suggesting it has not yet been widely exploited in the wild. Nonetheless, because the flaw can be triggered by any keystore consumer, the attack vector is likely local or remote code execution through a malformed file. Administrators should evaluate whether they process untrusted keystore inputs before applying the mitigations.
