cmov: cmov: Incorrect output due to improper zero-extension in aarch64 conditional move operations

A flaw was found in the cmov component of RustCrypto. The aarch64 implementations of Cmov and CmovEq incorrectly assume that high bits are zero-extended when loading values smaller than a register. This can lead to incorrect output when certain high bits are set in a Cmov selector or in the u16 a...

CVE-2026-50185

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. From 0.1.1 until 0.5.4, the aarch64 implementations of Cmov and CmovEq in cmov/src/backends/aarch64.rs assume high bits ar...

CVE-2026-50185 RustCrypto Cmov/CmovEq on aarch64 can produce wrong results if high-bits of registers are set

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. From 0.1.1 until 0.5.4, the aarch64 implementations of Cmov and CmovEq in cmov/src/backends/aarch64.rs assume high bits ar...

CVE-2026-50185

CVE-2026-50185 affects RustCrypto CMOV (cmov crate) aarch64 backends where Cmov and CmovEq incorrectly assume high bits are zero-extended when loading small values, causing left.cmovz and cmoveq operations to produce incorrect results under certain casts or inline-asm paths. Affected range is 0.1...

CVE-2026-50185 RustCrypto Cmov/CmovEq on aarch64 can produce wrong results if high-bits of registers are set

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. From 0.1.1 until 0.5.4, the aarch64 implementations of Cmov and CmovEq in cmov/src/backends/aarch64.rs assume high bits ar...

CVE-2026-50185

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. From 0.1.1 until 0.5.4, the aarch64 implementations of Cmov and CmovEq in cmov/src/backends/aarch64.rs assume high bits ar...

EUVD-2026-45254

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. From 0.1.1 until 0.5.4, the aarch64 implementations of Cmov and CmovEq in cmov/src/backends/aarch64.rs assume high bits ar...

Cmov/CmovEq on aarch64 can produce wrong results if high-bits of registers are set

Summary The aarch64 implementations of Cmov and CmovEq seem to assume that the high bits when loading a value of size smaller than a register into a register are zero-extended. However, this is not the case and these bits are unspecified. This can result in a left.cmovz&right, condition not movin...

PT-2026-55351

Summary The aarch64 implementations of Cmov and CmovEq seem to assume that the high bits when loading a value of size smaller than a register into a register are zero-extended. However, this is not the case and these bits are unspecified. This can result in a left.cmovz&right, condition not movin...

CVE-2026-23519

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...

CVE-2026-23519

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...

CVE-2026-23519

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...

CVE-2026-23519

The CVE-2026-23519 entry describes RustCrypto CMOV, which provides conditional move CPU intrinsics. The vulnerability concerns the thumbv6m-none-eabi target (Cortex-M0, M0+, M1) where the compiler emitted non-constant-time assembly for cmovnz prior to version 0.4.4. The issue affects how conditio...

CVE-2026-23519 RustCrypto cmov: thumbv6m-none-eabi compiler emits non-constant time assembly when using cmovnz

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...

GHSA-2GQC-6J2Q-83QP RustCrypto Utilities cmov: `thumbv6m-none-eabi` compiler emits non-constant time assembly when using `cmovnz`

Summary thumbv6m-none-eabi Cortex M0, M0+ and M1 compiler emits non-constant time assembly when using cmovnz portable version. I did not found any other target with the same behaviour but I did not go through all targets supported by Rust. Details It seems that, during mask computation, an LLVM...

RustCrypto Utilities cmov: `thumbv6m-none-eabi` compiler emits non-constant time assembly when using `cmovnz`

Summary thumbv6m-none-eabi Cortex M0, M0+ and M1 compiler emits non-constant time assembly when using cmovnz portable version. I did not found any other target with the same behaviour but I did not go through all targets supported by Rust. Details It seems that, during mask computation, an LLVM...