Red Hat Firefox 140.15 Update Addresses Ten RHEL 10 Vulnerabilities

P1 — VALIDATE AND UPDATEMedium to High · 6.1 / 7.5 (CVSS v3.1)EXPLOITATION: NOT STATED

Quick Answer

Red Hat published RHSA-2026:77610 for Firefox ESR on RHEL 10.0 Extended Update Support. Inventory the exact affected scope, apply firefox 140.15.0-1.el10_0 for the matching entitled RHEL 10.0 EUS architecture, validate dependent operations, and preserve change evidence.

Validate Firefox Scope And Apply The Supported Fix

What to do now: Inventory Firefox ESR on RHEL 10.0 Extended Update Support, match versions and enabled features to the authority's scope, apply supported remediation, validate representative operations, and document exceptions.

Open the authoritative advisory

Last verified: 2026-10-07 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.

Scope And Authority

Product scopeFirefox ESR on RHEL 10.0 Extended Update Support
AdvisoryRHSA-2026:77610
CVEsCVE-2026-16365, CVE-2026-75874, CVE-2026-84119, CVE-2026-84120, CVE-2026-84121, CVE-2026-84122, CVE-2026-84124, CVE-2026-84131, CVE-2026-84143, CVE-2026-84145
Authoritative release date2026-10-07 14:05:01 UTC
Authority revision date2026-10-07 14:10:16 UTC
Affected versionsThe exact supported Firefox ESR on RHEL 10.0 Extended Update Support builds marked affected in the advisory product-status relationships.
Fixed versionfirefox 140.15.0-1.el10_0 for the matching entitled RHEL 10.0 EUS architecture
CVSS base score6.1 / 7.5 (CVSS v3.1)
CVSS severityMedium to High
Exploitation statusNot stated by the authority; no exploitation claim is inferred.

What Changed

Red Hat published an authority-rated Important Firefox security update with branch-specific fixed content for the listed CVEs.

What To Validate Now

  1. Inventory. Locate Firefox ESR on RHEL 10.0 Extended Update Support; record versions, enabled features, exposure paths, owners, dependencies, support channels, and maintenance groups.
  2. Establish applicability. Compare every deployment with the authority's affected statement: The exact supported Firefox ESR on RHEL 10.0 Extended Update Support builds marked affected in the advisory product-status relationships. Do not infer applicability from product family, CVSS, or Internet reachability alone.
  3. Remediate. Apply firefox 140.15.0-1.el10_0 for the matching entitled RHEL 10.0 EUS architecture through the authority-supported channel and follow the current advisory.
  4. Validate. Confirm the resulting Firefox build or managed state, exercise representative services and recovery paths, monitor for regressions, and retain the result.
  5. Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.

Operational Cautions

Follow the entitled Red Hat update channel and verify package or image relationships for the exact product branch. Preserve pre-change state, installation output, logs, validation evidence, and rollback decisions.

Evidence To Retain

  • Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
  • UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
  • Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.

Related TechGeeks Resources

Authoritative References

Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.