Cyber Resilience

CVE-2026-92050

Race Condition in Mozilla Firefox ≤ 156.0.0

Published
15 September 2026
Modified
05 October 2026
Patch / advisory
CVSS Score v3.1 9.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
EPSS Score 0.0044 36th percentile
Risk Priority 67 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-92050 is a critical-severity Race Condition (CWE-362) vulnerability in Mozilla Firefox. Its CVSS base score is 9.1 (Critical).

Operationally, ranked at the 36th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-39 (Process Isolation) and SC-4 (Information in Shared System Resources) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Sandbox escape due to race condition in the XPConnect component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.

CWE(s)

Related Threats

CVEs Like This One

CVE-2024-38613Shared CWE-362
CVE-2026-23735Shared CWE-362
CVE-2026-65415Shared CWE-362
CVE-2024-21601Shared CWE-362
CVE-2026-23240Shared CWE-362
CVE-2025-37920Shared CWE-362
CVE-2024-46734Shared CWE-362
CVE-2025-7954Shared CWE-362
CVE-2025-54919Shared CWE-362
CVE-2025-43304Shared CWE-362

Affected Assets

mozilla
firefox
≤ 156.0.0
mozilla
thunderbird
≤ 156.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V10.4.2
  • V15.1.3
  • V15.4.1
  • V15.4.2

Mitigating Controls (NIST 800-53 r5) AI

Maintaining separate execution domains for each process structurally eliminates unintended concurrent access to the same shared resources.

Preventing unintended information transfer through shared system resources directly addresses the improper concurrent modification that defines a race condition.

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.

PR.PS-06 partial match
prevents

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.

prevents

A.8.25 mandates secure SDLC practices (secure coding guidelines, security requirements, checkpoints, testing including code scans/penetration tests, developer training) that reach race conditions in concurrent code, but only as one slice of a broad requirement whose implementation scope and rigour are left to the organisation.

prevents

A.8.26 explicitly lists resilience against malicious attacks including SQL injections and input validation as application security requirements to identify/address; race conditions are a similar class of timing-based concurrency flaw that can be mitigated by requirements for proper synchronization/locking, but this is only one slice of the broad CWE-362 class (most instances arise in low-level shared-memory or TOCTOU scenarios not named here).

prevents

Secure architecture principles require proper synchronization and resource isolation, addressing the root cause of CWE-362.

prevents

Secure coding standards explicitly forbid unsafe concurrent access patterns and mandate atomic operations or locks.

finds

Security testing can detect race conditions, but does not prevent them at design or coding time.

References