Answer in brief
CVE-2026-4720 records a Critical severity (CVSS 9.8) memory corruption vulnerability in CVE-2026-4720. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
Answer in brief
CVE-2026-4720 records a Critical severity (CVSS 9.8) memory corruption vulnerability in CVE-2026-4720. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
Memory Corruption describes the vulnerability class recorded for this advisory. The current record does not mark CVE-2026-4720 as known exploited; continue to monitor the source for status changes. This is a product-level record in the current feed, not a package-level dependency mapping.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
Memory safety bugs present in 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 140.9, Thunderbird 149, and Thunderbird 140.9.
Reported by NVD (nvd).
CVE-2026-4720 records a Critical severity (CVSS 9.8) memory corruption vulnerability in CVE-2026-4720. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
The source record does not mark it as known exploited.
Confirm whether the product or interface named by this advisory exists in your inventory.
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL GuardReview the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
Memory Corruption describes the vulnerability class recorded for this advisory. The current record does not mark CVE-2026-4720 as known exploited; continue to monitor the source for status changes. This is a product-level record in the current feed, not a package-level dependency mapping.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
Memory safety bugs present in 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 140.9, Thunderbird 149, and Thunderbird 140.9.
Reported by NVD (nvd).
CVE-2026-4720 records a Critical severity (CVSS 9.8) memory corruption vulnerability in CVE-2026-4720. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
The source record does not mark it as known exploited.
Confirm whether the product or interface named by this advisory exists in your inventory.
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL Guard