CVE-2021-21166
Race Condition in Fedoraproject Fedora 32 … 34
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HSummary
CVE-2021-21166 is a high-severity Race Condition (CWE-362) vulnerability in Fedoraproject Fedora. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
The vulnerability is a data race in the audio component of Google Chrome, tracked as CWE-362, that affects all versions prior to 89.0.4389.72. The flaw can result in heap corruption when processing certain inputs.
A remote attacker can exploit the issue by convincing a user to visit a crafted HTML page. Successful exploitation may allow the attacker to achieve heap corruption with high impact on confidentiality, integrity, and availability, as reflected in the CVSS 8.8 score requiring only user interaction and no other privileges.
The referenced Chrome stable channel update and Fedora package advisories indicate that the issue is resolved by upgrading to Chrome 89.0.4389.72 or later, with corresponding updates distributed through standard package channels for affected Linux distributions. No information on observed in-the-wild exploitation is provided in the references.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-8557
Vulnerability Data
Data race in audio in Google Chrome prior to 89.0.4389.72 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
- CWE(s)
- KEV Date Added
- 03 November 2021
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Accurate timestamps from internal clocks enable detection of race conditions by providing reliable event ordering in audit logs.
Coordination of concurrent security activities reduces the probability that shared resources will be accessed simultaneously without proper synchronization.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly require proper synchronization primitives and concurrency testing that prevent race conditions.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect race conditions, but does not prevent them at design or coding time.
Secure SDLC mandates concurrency controls and synchronization primitives that directly prevent race conditions.
Application security requirements can specify thread-safety and locking rules, but do not prescribe implementation details.
Secure architecture principles require proper synchronization and resource isolation, addressing the root cause of CWE-362.
Secure coding standards explicitly forbid unsafe concurrent access patterns and mandate atomic operations or locks.
Change management reduces introduction of concurrency bugs during updates, yet does not address the weakness itself.