Cyber Resilience

CVE-2026-92017

Mozilla Firefox ≤ 115.41.0

Published
15 September 2026
Modified
06 October 2026
Patch / advisory
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0026 16th percentile
Risk Priority 63 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-2026-92017 is a high-severity Improper Privilege Management (CWE-269) vulnerability in Mozilla Firefox. Its CVSS base score is 8.8 (High).

Operationally, ranked at the 16th 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 AC-16 (Security and Privacy Attributes) and AC-2 (Account Management) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-66314Shared CWE-269
CVE-2023-37389Shared CWE-269
CVE-2026-9193Shared CWE-269
CVE-2023-45253Shared CWE-269
CVE-2026-46970Shared CWE-269
CVE-2026-60566Shared CWE-269
CVE-2023-31432Shared CWE-269
CVE-2026-46804Shared CWE-269
CVE-2024-1575Shared CWE-269
CVE-2024-21118Shared CWE-269

Affected Assets

mozilla
firefox
≤ 115.41.0 · 116.0 — 140.16.0 · 141.0 — 153.3.0
mozilla
thunderbird
≤ 140.16.0 · 141.0 — 153.3.0 · 154.0 — 156.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

Binding security attributes to subjects/objects supplies the mechanism needed to track and enforce privileges correctly.

Account management directly governs assignment and tracking of privileges so proper implementation stops the weakness from being introduced.

Requiring explicit access-control decisions ensures privileges are evaluated rather than assumed or omitted.

Access enforcement applies the correct privilege checks at every request, structurally preventing unintended spheres of control.

Separation of duties constrains how privileges may be assigned, reducing the chance of overly broad actor control.

Least privilege is the direct countermeasure to improper privilege management; implementing it eliminates the root cause.

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.AA-05 mostly match
prevents

PR.AA-05 enforces least privilege/SoD and periodic reviews that directly remove most privilege-assignment defects, yet CWE-269 also covers escalation paths and role design outside a single access-management control.

PR.AA-01 partial match
prevents

PR.AA-01 supplies credential/identity lifecycle support that can reduce some privilege-assignment errors but does not itself assign, modify, or check privileges, leaving most of CWE-269's risk unaddressed.

PR.PS-01 partial match
prevents

Config baselines and default reviews can enforce some privilege-related settings (one facet) but do not address code-level assignment/tracking logic that defines CWE-269.

PR.PS-05 partial match
prevents

PR.PS-05 can partially limit exploitability of some privilege issues via execution restrictions, but does not address the core design/implementation flaws of CWE-269 at all.

PR.DS-10 none match
prevents

PR.DS-10 protects data-in-use without touching privilege assignment/tracking, so it neither prevents CWE-269 nor removes more than one narrow facet of its risk.

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.5.15 directly mandates determining access requirements, defining/enforcing topic-specific access control policy, assigning rights/restrictions by entity/role, consistency with classification, need-to-know, privileged access restrictions, segregation, formal authorization, and dynamic rules — which stops most improper privilege management from being exploitable; bounded remainder is flawed implementation of those rules (e.g. incorrect mapping or enforcement bugs).

prevents

A.5.18 directly governs the provisioning, review, modification and timely revocation of access rights (including for role changes, termination and privilege levels), which stops most improper privilege spheres from being exploitable even if the assignment flaw exists; the bounded remainder is flaws in the underlying enforcement mechanism itself (e.g. AC-3/A.8.3)

prevents

Defining and communicating authorization levels for each role limits the assignment of excessive or unnecessary privileges.

A.8.15 Logging partial match
finds

Logging every use of privileges and protecting those records makes it harder for an attacker who has obtained elevated rights to operate without leaving evidence.

prevents

A.8.2 directly controls the identification, allocation, review, expiry, temporary use, and separation of privileged rights per policy, which prevents most improper privilege management (CWE-269) by design; the bounded remainder is flawed tracking/checking logic inside the product's own enforcement code (the AC-3 slice of 269).

prevents

A.8.27 mandates security-by-design principles including least privilege, default deny, fail securely, defence in depth, security architecture integration, hardening, and zero-trust verification of every request; these directly stop most improper privilege spheres from being exploitable even if the assignment flaw remains, with a bounded remainder (e.g. certain legacy or safety-overridden controls).

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

Windows 10 (1 rule)
  • V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows Server 2016 (1 rule)
  • V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-269
Windows Server 2019 (1 rule)
  • V-205746 Windows Server 2019 must only allow Administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269

References