CVE-2026-100789
published 2026-09-29CVE-2026-100789: Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4…
PriorityP346high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.34%
25.9th percentile
Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox_esr | < Firefox ESR 153.4 | Firefox ESR 153.4 |
| mozilla | firefox_esr | < Firefox ESR 115.42 | Firefox ESR 115.42 |
| mozilla | firefox_esr | < Firefox ESR 140.17 | Firefox ESR 140.17 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat8.8HIGH
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GHSA
Use-after-free in the Graphics: Canvas2D component.
ghsa_unreviewed·2026-09-29
CVE-2026-100789 [HIGH] CWE-416 Use-after-free in the Graphics: Canvas2D component.
Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Red Hat
firefox: thunderbird: Use-after-free in the Graphics: Canvas2D component
vendor_redhat·2026-09-29·CVSS 8.8
CVE-2026-100789 [HIGH] CWE-825 firefox: thunderbird: Use-after-free in the Graphics: Canvas2D component
firefox: thunderbird: Use-after-free in the Graphics: Canvas2D component
Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Use-after-free in the Graphics: Canvas2D component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird (Red Hat Enterprise Linux 6) - Out of support sc
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-97: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100789
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-102: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100789
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-100: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100789
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-103: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100789
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-98: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-98: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-98
CVE: CVE-2026-100789
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 115.42
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-101: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100789
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100789
vendor_mozilla·CVSS 8.8
CVE-2026-100789 [HIGH] Mozilla Foundation Security Advisory 2026-99: CVE-2026-100789
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100789
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2072429https://www.mozilla.org/security/advisories/mfsa2026-100/https://www.mozilla.org/security/advisories/mfsa2026-101/https://www.mozilla.org/security/advisories/mfsa2026-102/https://www.mozilla.org/security/advisories/mfsa2026-103/https://www.mozilla.org/security/advisories/mfsa2026-97/https://www.mozilla.org/security/advisories/mfsa2026-98/https://www.mozilla.org/security/advisories/mfsa2026-99/
2026-09-29
Published