CyberRota Analysis
AI-GeneratedBouncy Castle for Java versions prior to 1.86 are vulnerable due to improper handling of secret values in the NTRU cryptographic algorithm, where timing variations in integer division can leak information about the private key. This vulnerability allows attackers to exploit timing side-channel attacks to recover sensitive key material, posing a significant risk to applications relying on NTRU for encryption. Organizations using Bouncy Castle for cryptographic operations should prioritize updating to version 1.86 or later to mitigate this high-severity risk.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a variable divisor, which a compiler cannot strength-reduce to a multiply the way it can a constant one, so it emitted a division on every call including on the decapsulation path where the dividend derives from the private key; Polynomial.mod3 and NTRUSampling.mod3 divided the secret key polynomials f and g during key generation, the message polynomials r and m during encapsulation, and coefficients recovered during decapsulation. An attacker able to measure that timing can recover information about the NTRU private key. modQ now masks, which is exact because q is always a power of two, and mod3 uses the reference implementation's division-free fold and select; the results are unchanged.