CVE-2026-10512: wolfSSL

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

The X25519 x86_64 assembly implementation fails to clear the most significant bit during the final modular reduction, so the computed result may not be fully reduced modulo the field prime 2^255 - 19. This can leave the field element in a non-canonical form, producing an incorrect result from the scalar multiplication and potentially a wrong shared secret. The final carry-propagation chains in the x64 and AVX2 reduction routines could overflow into the top bit, and the high limb was not masked afterward, so the 255-bit field element was left non-canonical.

Affected products

• wolfSSL wolfSSL: from 5.6.4, before 5.9.2 (fixed in 5.9.2)

Published 2026-06-25. Last modified 2026-06-26.