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 are zero-extended when loading values smaller than a register, so set high bits such as [8..] in a Cmov selector or [16..] of self or other in the u16 and i16 CmovEq implementations can cause left.cmovz(&right, condition) to produce incorrect output. This issue is fixed in version 0.5.4.

CVSS v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.8 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/RustCrypto/utils/commit/dba6c355c9f241e3726d5ec2a68f9f3b519f6063	Patch
https://github.com/RustCrypto/utils/releases/tag/cmov-v0.5.4	Product
https://github.com/RustCrypto/utils/security/advisories/GHSA-3rjw-m598-pq24	Exploit Vendor Advisory
https://github.com/RustCrypto/utils/security/advisories/GHSA-3rjw-m598-pq24	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:rustcrypto:cmov:*:*:*:*:*:rust:*:*

History

No history.

Information

Published : 2026-07-17 19:17

Updated : 2026-08-18 16:03

NVD link : CVE-2026-50185

Mitre link : CVE-2026-50185

CVE.ORG link : CVE-2026-50185

JSON object : View

Products Affected

rustcrypto

cmov

CWE

CWE-758

Reliance on Undefined, Unspecified, or Implementation-Defined Behavior

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