CVE-2026-117921
published 2026-10-27CVE-2026-117921: Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird…
PriorityP426
EPSS
0.19%
8.3th percentile
Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 159 | Firefox 159 |
| mozilla | firefox_esr | < Firefox ESR 115.44 | Firefox ESR 115.44 |
| mozilla | firefox_esr | < Firefox ESR 153.6 | Firefox ESR 153.6 |
| mozilla | thunderbird | < Thunderbird 153.6 | Thunderbird 153.6 |
| mozilla | thunderbird | < Thunderbird 159 | Thunderbird 159 |
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Mozilla
Mozilla Foundation Security Advisory 2026-118: CVE-2026-117921
vendor_mozilla
CVE-2026-117921 Mozilla Foundation Security Advisory 2026-118: CVE-2026-117921
Mozilla Foundation Security Advisory 2026-118
CVE: CVE-2026-117921
Product: Firefox
Impact: low
Fixed in: Firefox 159
Mozilla
Mozilla Foundation Security Advisory 2026-122: CVE-2026-117921
vendor_mozilla
CVE-2026-117921 Mozilla Foundation Security Advisory 2026-122: CVE-2026-117921
Mozilla Foundation Security Advisory 2026-122
CVE: CVE-2026-117921
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.6
Mozilla
Mozilla Foundation Security Advisory 2026-119: CVE-2026-117921
vendor_mozilla
CVE-2026-117921 Mozilla Foundation Security Advisory 2026-119: CVE-2026-117921
Mozilla Foundation Security Advisory 2026-119
CVE: CVE-2026-117921
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 115.44
Mozilla
Mozilla Foundation Security Advisory 2026-120: CVE-2026-117921
vendor_mozilla
CVE-2026-117921 Mozilla Foundation Security Advisory 2026-120: CVE-2026-117921
Mozilla Foundation Security Advisory 2026-120
CVE: CVE-2026-117921
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.6
Mozilla
Mozilla Foundation Security Advisory 2026-121: CVE-2026-117921
vendor_mozilla
CVE-2026-117921 Mozilla Foundation Security Advisory 2026-121: CVE-2026-117921
Mozilla Foundation Security Advisory 2026-121
CVE: CVE-2026-117921
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 159
GHSA
Use-after-free in the CSS Parsing and Computation component.
ghsa_unreviewed·2026-10-27
CVE-2026-117921 Use-after-free in the CSS Parsing and Computation component.
Use-after-free in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2079687https://www.mozilla.org/security/advisories/mfsa2026-118/https://www.mozilla.org/security/advisories/mfsa2026-119/https://www.mozilla.org/security/advisories/mfsa2026-120/https://www.mozilla.org/security/advisories/mfsa2026-121/https://www.mozilla.org/security/advisories/mfsa2026-122/
2026-10-27
Published