crypto: ecc - Fix carry overflow in vli multiplication
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.8epss 0.3%
exploitation probability
0.3%top 73% of all CVEs
observed exploitation
nono source reports it
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:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Linux · LinuxReferences
https://git.kernel.org/stable/c/24a54dfa06d09813b4802a374fad3d2c0e16a884https://git.kernel.org/stable/c/27b536a2ec8e2f85a0380c2d13c9ecbc7aaab406https://git.kernel.org/stable/c/5275e0fca256d081e2e7d4ba3dd8216c6e50d44ehttps://git.kernel.org/stable/c/677450e5ef850c4d28b7956aa01104548c2a894ehttps://git.kernel.org/stable/c/774ddddf5eb26eeca177350413e3e2bc50930ee9https://git.kernel.org/stable/c/b709e0e768766abe29a49e1c1922a1604be602f4https://git.kernel.org/stable/c/d11b2bb99bec1f5557c01cac42231e23745f49b8https://git.kernel.org/stable/c/ebaae7c4251cc0cdb2602f334d4f08a3e82d271e