Cyber Resilience

CVE-2025-10536

Info Disclosure in Mozilla Firefox ≤ 140.3.0

Published
16 September 2025
Modified
13 April 2026
Patch / advisory
CVSS Score v3.1 6.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0015 5th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2025-10536 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Mozilla Firefox. Its CVSS base score is 6.2 (Medium).

Operationally, ranked at the 5th 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 AU-13 (Monitoring for Information Disclosure) and SI-2 (Flaw Remediation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Information disclosure in the Networking: Cache component. This vulnerability was fixed in Firefox 143, Firefox ESR 140.3, Thunderbird 143, and Thunderbird 140.3.

CWE(s)

Related Threats

CVEs Like This One

CVE-2026-6782Same product: Mozilla Firefox
CVE-2024-6612Same product: Mozilla Firefox
CVE-2026-8965Same product: Mozilla Firefox
CVE-2026-0883Same product: Mozilla Firefox
CVE-2026-8967Same product: Mozilla Firefox
CVE-2026-16354Same product: Mozilla Firefox
CVE-2026-16374Same product: Mozilla Firefox
CVE-2026-6770Same product: Mozilla Firefox
CVE-2026-8966Same product: Mozilla Firefox
CVE-2025-8039Same product: Mozilla Firefox

Affected Assets

mozilla
firefox
≤ 140.3.0 · ≤ 143.0
mozilla
thunderbird
≤ 140.3.0 · 141.0 — 143.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-2 Flaw Remediation
  • SC-28 Protection of Information at Rest
Detect
Catch it (NIST detect / respond)
  • AU-13 Monitoring for Information Disclosure
Harden
Shrink the surface (DISA STIG)
  • 7 hardening rules · 6 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V10.4.9
  • V11.7.1
  • V14.1.2
  • V14.2.4

Mitigating Controls (NIST 800-53 r5) AI

detect

Directly monitors systems for unauthorized exposure of sensitive information, matching the cache-based disclosure in this CVE.

prevent

Requires prompt installation of vendor patches that eliminate the information disclosure flaw in the Networking: Cache component.

prevent

Mandates cryptographic or access protections for data at rest, reducing exposure risk from cached network objects.

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 directly enforces least-privilege authorization that blocks most unauthorized disclosures, yet CWE-200 also arises from logging, error messages, and side-channel paths that access controls alone do not address.

PR.DS-10 mostly match
prevents

PR.DS-10 mostly prevents CWE-200 by directly eliminating unauthorized access to sensitive data-in-use, yet only partially addresses the weakness because CWE-200 spans many other exposure vectors outside runtime protection.

PR.IR-01 mostly match
prevents

PR.IR-01's segmentation/zero-trust controls largely eliminate network-level unauthorized access paths that enable exposure, yet CWE-200 spans many additional vectors (API responses, logs, app logic) that network controls alone cannot close.

PR.PS-06 mostly match
prevents

Secure SDLC practices catch most exposure flaws via design, testing and release controls, yet CWE-200 spans runtime/config issues a single development outcome cannot fully close.

PR.AA-01 partial match
prevents

PR.AA-01 supplies proper credential lifecycle controls that reduce unauthorized access paths, yet leaves many other exposure vectors (error messages, logging, side channels, etc.) unaddressed.

PR.AA-03 partial match
prevents

Authentication verifies actor identity and is a prerequisite for access decisions, yet addresses only one facet of the broad set of exposure vectors in CWE-200.

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

Restricting anonymous or unknown access and encrypting high-value information limits the exposure of sensitive data that would otherwise be obtainable by unauthorized actors.

prevents

Suppressing system details, error specifics, and previous log-on information until successful authentication reduces the information an unauthenticated attacker can gather.

prevents

By requiring owners to assign sensitivity labels and corresponding handling rules, the control ensures that information is not left unmarked and therefore reduces the chance that sensitive data will be exposed to unauthorized actors.

prevents

Requiring encryption, access controls, and recipient authentication for transfers directly reduces the chance that sensitive data reaches an unauthorized observer.

prevents

Secure delivery, protected storage, and confidentiality of allocation records limit exposure of authentication material to unauthorized observers.

prevents

Requiring defined procedures, assigned roles, and technical/organizational measures for handling PII reduces the chance that sensitive personal data will be exposed to unauthorized actors through inadequate handling or missing safeguards.

References