Description
RustCrypto CMOV provides conditional move CPU intrinsics which are guaranteed on major platforms to execute in constant-time and not be rewritten as branches by the compiler. Prior to 0.4.4, the thumbv6m-none-eabi (Cortex M0, M0+ and M1) compiler emits non-constant time assembly when using cmovnz (portable version). This vulnerability is fixed in 0.4.4.
Scores
CVSS v3
9.8
EPSS
0.0003
EPSS Percentile
8.7%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-208
CWE-203
Status
published
Products (2)
crates.io/cmov
0 - 0.4.4crates.io
rustcrypto/cmov
< 0.4.4
Published
Jan 15, 2026
Tracked Since
Feb 18, 2026