CVE-2021-1782 is a race condition vulnerability in Apple Multiple Products. CISA added it to the Known Exploited Vulnerabilities catalogue on 3 November 2021, which means attackers have used it in real attacks. Apple iOS, iPadOs, macOS, watchOS, and tvOS contain a race condition vulnerability that may allow a malicious application to elevate privileges.
What this race condition means in Apple products
A race condition appears when two execution paths compete over the same state and the result depends on timing rather than design. In Apple’s case, that timing flaw in iOS, iPadOS, macOS, watchOS, and tvOS could let a malicious app gain elevated privileges if it wins the race at the right moment.
This matters because privilege boundaries are supposed to stop an app from crossing from its own sandbox or permission set into system-level capabilities. When timing logic is flawed, the security decision can be bypassed even though the code path looks legitimate under normal conditions.
Why race conditions are dangerous in mobile and desktop platforms
Race conditions are especially risky in operating systems because they often sit in code that manages access, process state, or security-sensitive transitions. A flaw that is hard to trigger during testing can still be practical for attackers when they can repeat the same sequence many times until the timing aligns.
For end users, the danger is not just application crash or instability. If the race affects privilege enforcement, an attacker may be able to move from a normal app context into a more trusted system context, which can expose data, weaken device protections, or create a foothold for further compromise. The CWE Top 25 Guide is useful background because race conditions are a recurring weakness class, not just a one-off bug.
How organisations check exposure and decide whether the issue matters
Exposure review starts with knowing which Apple products and versions exist in the estate, then checking whether any vulnerable devices are internet-reachable, externally managed, or used for high-value work. Vendor advisories and authoritative vulnerability records are the right source for affected-version and remediation details, not informal summaries.
For vulnerability triage, the most useful question is whether the affected device is actively in use and whether an untrusted app can be installed or executed on it. Apple platform flaws can become enterprise issues quickly when BYOD fleets, mobile app stores, or unmanaged endpoints are involved. Use the NIST National Vulnerability Database and the CVE Program to anchor the record, then follow Apple’s advisory for the exact remediation path.
Remediation, detection, and post-exploitation review
The primary remediation is to apply the vendor fix as soon as it is available and practical. When patching is delayed, reduce exposure by limiting app installation paths, tightening device management policy, and restricting access to sensitive services from untrusted or outdated devices. The vulnerability should be treated as exploitation-prone because CISA added it to the KEV catalogue, which signals real-world abuse.
Detection is usually indirect: look for suspicious app behaviour, privilege-related crashes, unexpected security setting changes, or signs that a low-privilege app began acting with unusual authority. After patching, review the device for persistence, malicious configuration changes, and any accounts, sessions, or secrets that may have been accessed during elevated execution. On managed fleets, the Vulnerability Management Guide is a useful companion for prioritisation, verification, and remediation tracking.
Risk and Threat Considerations
Because this flaw can elevate privileges, the main risk is that a seemingly ordinary app can cross into a trusted operating context and bypass the protections users rely on. In enterprise or personal environments, that can turn a single compromised app install into broader device compromise.
Failure mechanism: The attacker abuses timing-sensitive execution to make the operating system take an unsafe branch, then uses the resulting elevated context to access protected resources or alter security state.
Impact: The device may be exposed to data theft, persistent compromise, stronger malware installation, or follow-on abuse of credentials and sessions stored on the endpoint.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
CIS Controls v8, NIST SP 800-53 Rev 5 and NIST CSF 2.0 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| CIS Controls v8 | CIS-4 — Secure Configuration of Enterprise Assets and Software | Race-condition exposure is reduced by hardened platform configuration and controlled software deployment. |
| Recommendation — Harden Apple endpoint baselines and restrict software installation paths. | ||
| NIST SP 800-53 Rev 5 | SI-2 — Flaw Remediation | This CVE requires timely remediation and verification of the vendor fix across affected devices. |
| SI-4 — System Monitoring | Post-exploitation review depends on monitoring for abnormal privilege-related behaviour after compromise. | |
| CM-6 — Configuration Settings | Compensating controls rely on restricting risky configuration and limiting app execution paths. | |
| Recommendation — Track and apply the Apple fix, then verify remediation across the fleet. Monitor endpoints for privilege anomalies and suspicious post-patch activity. Constrain endpoint settings to reduce untrusted app execution and exposure. | ||
| NIST CSF 2.0 | PR.IP-12 — Vulnerability Management | The vulnerability must be identified, prioritised and remediated within a managed vulnerability process. |
| Recommendation — Prioritise and remediate the Apple race-condition flaw through your vulnerability program. | ||
Practitioner Guidance
Why practitioners should care: Race-condition bugs are often operationally underestimated because they can be intermittent in testing yet highly usable in exploitation. In a platform OS, that makes prioritisation depend less on how often the flaw reproduces in the lab and more on how much trust the affected device holds in production.
Practitioner takeaway: Treat privilege-escalation race conditions on widely deployed endpoints as high-priority remediation items, then verify whether any app, account, or session data on those devices needs follow-up review after patching.