Cyber Posture

CVE-2026-6782

High

Published: 21 April 2026

Published
21 April 2026
Modified
22 April 2026
KEV Added
Patch
CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0004 12.3th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-6782 is a high-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Mozilla Firefox. Its CVSS base score is 7.5 (High).

Operationally, ranked at the 12.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 RA-5 (Vulnerability Monitoring and Scanning) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly requires timely identification, reporting, and patching of software flaws like CVE-2026-6782, preventing exploitation by updating to Firefox/Thunderbird 150.

detect

Mandates vulnerability scanning to identify unpatched instances of CVE-2026-6782 in deployed Firefox and Thunderbird installations.

detect

Requires monitoring and distribution of security advisories such as MFSA 2026-30/33, enabling prompt awareness and remediation of CVE-2026-6782.

MITRE ATT&CK Enterprise TechniquesAI

Insufficient information to map techniques.
Confidence: LOW · MITRE ATT&CK Enterprise v18.1

NVD Description

Information disclosure in the IP Protection component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Deeper analysisAI

CVE-2026-6782 is an information disclosure vulnerability (CWE-200) in the IP Protection component of Mozilla Firefox and Thunderbird. Published on 2026-04-21, it carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), highlighting high confidentiality impact with no effect on integrity or availability. The issue was fixed in Firefox version 150 and Thunderbird version 150.

Remote attackers can exploit this vulnerability over the network with low complexity, requiring no privileges or user interaction. Successful exploitation allows disclosure of sensitive information processed by the IP Protection component.

Mozilla's security advisories MFSA 2026-30 and MFSA 2026-33, along with Bugzilla entry 2026571, provide details on the vulnerability and recommend updating to the patched versions of Firefox 150 or Thunderbird 150 for mitigation.

Details

CWE(s)

Affected Products

mozilla
firefox
≤ 150.0
mozilla
thunderbird
≤ 150.0

CVEs Like This One

CVE-2026-6770Same product: Mozilla Firefox
CVE-2026-2803Same product: Mozilla Firefox
CVE-2026-2783Same product: Mozilla Firefox
CVE-2026-8093Same product: Mozilla Firefox
CVE-2025-9185Same product: Mozilla Firefox
CVE-2026-6766Same product: Mozilla Firefox
CVE-2025-1018Same product: Mozilla Firefox
CVE-2026-6773Same product: Mozilla Firefox
CVE-2025-8034Same product: Mozilla Firefox
CVE-2025-0241Same product: Mozilla Firefox

References