CVE-2026-100801
published 2026-09-29CVE-2026-100801: Privilege escalation in the DLL Services component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4…
PriorityP346high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.25%
15.1th percentile
Privilege escalation in the DLL Services component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | — | — |
| mozilla | firefox_esr | < Firefox ESR 140.17 | Firefox ESR 140.17 |
| mozilla | firefox_esr | < Firefox ESR 153.4 | Firefox ESR 153.4 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | — | — |
| rhel10 | firefox-flatpak | — | — |
| 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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Red Hat
firefox: thunderbird: Privilege escalation in the DLL Services component
vendor_redhat·2026-09-29·CVSS 8.8
CVE-2026-100801 [HIGH] CWE-269 firefox: thunderbird: Privilege escalation in the DLL Services component
firefox: thunderbird: Privilege escalation in the DLL Services component
Privilege escalation in the DLL Services component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Privilege escalation in the DLL Services component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Mitigation: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation bas
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100801
vendor_mozilla·CVSS 8.8
CVE-2026-100801 [HIGH] Mozilla Foundation Security Advisory 2026-101: CVE-2026-100801
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100801
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100801
vendor_mozilla·CVSS 8.8
CVE-2026-100801 [HIGH] Mozilla Foundation Security Advisory 2026-103: CVE-2026-100801
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100801
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100801
vendor_mozilla·CVSS 8.8
CVE-2026-100801 [HIGH] Mozilla Foundation Security Advisory 2026-99: CVE-2026-100801
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100801
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100801
vendor_mozilla·CVSS 8.8
CVE-2026-100801 [HIGH] Mozilla Foundation Security Advisory 2026-102: CVE-2026-100801
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100801
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100801
vendor_mozilla·CVSS 8.8
CVE-2026-100801 [HIGH] Mozilla Foundation Security Advisory 2026-100: CVE-2026-100801
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100801
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100801
vendor_mozilla·CVSS 8.8
CVE-2026-100801 [HIGH] Mozilla Foundation Security Advisory 2026-97: CVE-2026-100801
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100801
Product: Firefox
Impact: low
Fixed in: Firefox 157
GHSA
Privilege escalation in the DLL Services component.
ghsa_unreviewed·2026-09-29
CVE-2026-100801 [HIGH] CWE-269 Privilege escalation in the DLL Services component.
Privilege escalation in the DLL Services component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2057112https://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/mfsa2026-99/
2026-09-29
Published