Vulnerability in cmov (CVE-2026-50185)
Summary
Vulnerability in cmov (CVE-2026-50185). Risk of unauthorized operations or information disclosure. Exploitable via Cmov. Mitigation: upgrade to 0.5.4 or later.
Original description
The description as published by the source.
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.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-50185 has been found in cmov.
Attackers can target a specific entry point like Cmov over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 3.3/10.
What to do: upgrade cmov to 0.5.4 or later.
If unsure, ask your IT team or search "cmov CVE-2026-50185" on the vendor's site.
CVE-2026-50185 (cmov) — CWE-758 / CVSS v3 3.3
Attack vector: local / no user interaction
Attack surface: Cmov / CmovEq / right / left
Patched: 0.5.4 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-758) exists in cmov. Attackers reach the vulnerable code path via Cmov.
Check the vendor advisory for the affected versions of cmov. Attack surface: Cmov / CmovEq / right / left.
Severity: Low (CVSS 3.3/10). Risk of unauthorized operations or information disclosure.
Update to 0.5.4.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'cmov' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'cmov' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
cmovを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade cmov to 0.5.4ステージング環境で 0.5.4 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-50185 rust-cmov Fixed in: 0.5.4-1
- Ubuntu UBUNTU-CVE-2026-50185 rust-cmov
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- patch github.com
- web github.com
- web github.com