CVE-2026-64313
Published: July 29, 2026Last modified: August 14, 2026
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 8.8 |
| Attack Vector | ADJACENT_NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.182-r0) |
| 25 LTS | linux-lts | Fixed (6.12.103-r0) | |
| Stream | linux-lts | Fixed (6.18.43-r0) |
References
- https://git.kernel.org/stable/c/24a54dfa06d09813b4802a374fad3d2c0e16a884
- https://git.kernel.org/stable/c/27b536a2ec8e2f85a0380c2d13c9ecbc7aaab406
- https://git.kernel.org/stable/c/5275e0fca256d081e2e7d4ba3dd8216c6e50d44e
- https://git.kernel.org/stable/c/677450e5ef850c4d28b7956aa01104548c2a894e
- https://git.kernel.org/stable/c/774ddddf5eb26eeca177350413e3e2bc50930ee9
- https://git.kernel.org/stable/c/b709e0e768766abe29a49e1c1922a1604be602f4
- https://git.kernel.org/stable/c/d11b2bb99bec1f5557c01cac42231e23745f49b8
- https://git.kernel.org/stable/c/ebaae7c4251cc0cdb2602f334d4f08a3e82d271e