Is CVE-2026-4721 in the CISA KEV catalog?

No. CVE-2026-4721 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-4721?

CVE-2026-4721 has a CVSS v3 base score of 9.8 (CRITICAL).

What is the EPSS score for CVE-2026-4721?

CVE-2026-4721 has an EPSS score of 0.42% (34th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2026-4721?

Upgrade firefox on debian unstable to 149.0-1 or later. Fixes are available for 18 affected products.

CVE & CISA-KEV Catalog

CVE-2026-4721

CRITICAL

9.8

CVSS v3

NVD

Description

Memory safety bugs present in Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

CWE-120Classic Buffer Overflow CWE-825

How to fix

Remediation Available

firefoxDebian

Fixed in:149.0-1CVE-2026-4721

firefoxRocky

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el7_9RHSA-2026:8427

Fixed in:0:140.9.0-1.el7_9.ppc64RHSA-2026:8427

Fixed in:0:140.9.0-1.el7_9RHSA-2026:8427

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_4RHSA-2026:7858

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

firefoxRed Hat / RHEL

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el7_9RHSA-2026:8427

Fixed in:0:140.9.0-1.el7_9.ppc64RHSA-2026:8427

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_4RHSA-2026:7858

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

firefox-debuginfoRocky

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el7_9.ppc64RHSA-2026:8427

Fixed in:0:140.9.0-1.el7_9RHSA-2026:8427

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_4RHSA-2026:7858

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

firefox-debuginfoRed Hat / RHEL

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el7_9RHSA-2026:8427

Fixed in:0:140.9.0-1.el7_9.ppc64RHSA-2026:8427

Fixed in:0:140.9.0-1.el7_9RHSA-2026:8427

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_4RHSA-2026:7858

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

firefox-debugsourceRed Hat / RHEL

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el8_4RHSA-2026:7858

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

firefox-debugsourceRocky

Fixed in:0:140.9.0-1.el10_1RHSA-2026:5931

Fixed in:0:140.9.0-1.el10_0RHSA-2026:7843

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_2RHSA-2026:7840

Fixed in:0:140.9.0-1.el8_10RHSA-2026:5932

Fixed in:0:140.9.0-1.el8_4RHSA-2026:7858

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el8_8RHSA-2026:7838

Fixed in:0:140.9.0-1.el8_6RHSA-2026:7842

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_0RHSA-2026:7839

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

firefox-x11Red Hat / RHEL

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

firefox-x11Rocky

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_4RHSA-2026:7845

Fixed in:0:140.9.0-1.el9_6RHSA-2026:7837

Fixed in:0:140.9.0-1.el9_7RHSA-2026:5930

Fixed in:0:140.9.0-1.el9_2RHSA-2026:7841

thunderbirdRed Hat / RHEL

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_2RHSA-2026:8285

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

thunderbirdRocky

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_2RHSA-2026:8285

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

thunderbird-debuginfoRocky

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_2RHSA-2026:8285

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

thunderbird-debuginfoRed Hat / RHEL

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_2RHSA-2026:8285

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

thunderbird-debugsourceRed Hat / RHEL

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_2RHSA-2026:8285

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

thunderbird-debugsourceRocky

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el10_0RHSA-2026:8315

Fixed in:0:140.9.0-1.el10_1RHSA-2026:6342

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_4RHSA-2026:8850

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_10RHSA-2026:6917

Fixed in:0:140.9.0-1.el8_8RHSA-2026:8288

Fixed in:0:140.9.0-1.el8_6RHSA-2026:8289

Fixed in:0:140.9.0-1.el8_2RHSA-2026:8285

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_0RHSA-2026:8286

Fixed in:0:140.9.0-1.el9_4RHSA-2026:8290

Fixed in:0:140.9.0-1.el9_6RHSA-2026:8284

Fixed in:0:140.9.0-1.el9_7RHSA-2026:6188

Fixed in:0:140.9.0-1.el9_2RHSA-2026:8287

DeveloperEditionWindows application

Affected:128.0 140.9.0Fixed in:140.9.0Mozilla

Affected:149.0Fixed in:149.0Mozilla

Affected:115.34.0Fixed in:115.34.0Mozilla

Mozilla Firefox (en-US)Windows application

Affected:128.0 140.9.0Fixed in:140.9.0Mozilla

Affected:115.34.0Fixed in:115.34.0Mozilla

Affected:149.0Fixed in:149.0Mozilla

Mozilla Thunderbird (en-US)Windows application

Affected:149.0Fixed in:149.0Mozilla

Affected:140.9.0Fixed in:140.9.0Mozilla

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

0.42%probability of exploitation in 30 days

34thpercentile

Low risk: more likely to be exploited than 34% of all known CVEs.

References

Related Vulnerabilities

Other CWE-120 (Classic Buffer Overflow) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2014-0195	Medium	6.8	100%	-	Fix
CVE-2017-7269	Critical	9.8	100%	KEV	-
CVE-2019-11043	High	8.7	99%	KEV + Ransom	Fix
CVE-2011-4862	High	10.0	95%	-	Fix
CVE-2007-5659	High	7.8	94%	KEV	Fix
CVE-2022-3786	High	7.5	92%	-	Fix

Embed a live status badge for CVE-2026-4721

Markdown

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-07-15.