High severity · published Jul 25, 2026
CVE-2026-64313
crypto: ecc - Fix carry overflow in vli multiplication
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
4.8 before 5.10.261; 5.11 before 5.15.212; 5.16 before 6.1.178; 6.2 before 6.6.145; 6.7 before 6.12.96; 6.13 before 6.18.39; +1 more · source: NVD
LI
Linux · Linux
3c4b23901a0c766879dff680cd6bdab47bcdbbd2 before d11b2bb99bec1f5557c01cac42231e23745f49b8; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 before b709e0e768766abe29a49e1c1922a1604be602f4; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 before 24a54dfa06d09813b4802a374fad3d2c0e16a884; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 before 677450e5ef850c4d28b7956aa01104548c2a894e; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 before 5275e0fca256d081e2e7d4ba3dd8216c6e50d44e; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 before 774ddddf5eb26eeca177350413e3e2bc50930ee9; +3 more · source: vendor