In the Linux kernel, the following vulnerability has been resolved: crypto: ecc - Fix carry overflow in vli multiplication The carry flag calculation fails when r01.m_high is saturated (0xFFFFFFFFFFFFFFFF) and addition of lower bits overflows. The condition (r01.m_high < product.m_high) doesn't handle the case where r01.m_high == product.m_high and an additional carry exists from lower-bit overflow. When commit 3c4b23901a0c ("crypto: ecdh - Add ECDH software support") introduced crypto/ecc.c, it split the muladd() function in the micro-ecc library into separate mul_64_64() and add_128_128() helpers. It seems the check got lost in translation. Add proper handling for this boundary by accounting for the carry from the lower addition.

A flaw was found in the Linux kernel's Elliptic Curve Cryptography (ECC) component. An attacker on an adjacent network could exploit an error in the very long integer (vli) multiplication's carry flag calculation. This mathematical inaccuracy in cryptographic operations could lead to high impact on confidentiality, integrity, and availability.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Fix deferred kernel Red Hat Enterprise Linux 8 Fix deferred kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-64313 https://nvd.nist.gov/vuln/detail/CVE-2026-64313 https://lore.kernel.org/linux-cve-announce/2026072509-CVE-2026-64313-1119@gregkh/T