CVE-2026-74983
published 2026-08-18CVE-2026-74983: Mitigation bypass in the Data Loss Prevention component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154…
PriorityP342high8.1CVSS 3.1
AVNACLPRNUIRSUCHIHAN
EPSS
0.33%
25.7th percentile
Mitigation bypass in the Data Loss Prevention component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 154 | Firefox 154 |
| mozilla | firefox | < 140.14.0 | 140.14.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 141.0 < 153.1.0 | 153.1.0 |
| mozilla | firefox_esr | < Firefox ESR 140.14 | Firefox ESR 140.14 |
| mozilla | firefox_esr | < Firefox ESR 153.1 | Firefox ESR 153.1 |
| mozilla | thunderbird | < Thunderbird 153.1 | Thunderbird 153.1 |
| mozilla | thunderbird | < Thunderbird 140.14 | Thunderbird 140.14 |
| mozilla | thunderbird | < Thunderbird 154 | Thunderbird 154 |
| mozilla | thunderbird | < 140.14.0 | 140.14.0 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 141.0 < 153.1.0 | 153.1.0 |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
vendor_redhat3.4LOW
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
Red Hat
firefox: thunderbird: Mitigation bypass in the Data Loss Prevention component
vendor_redhat·2026-08-18·CVSS 3.4
CVE-2026-74983 [LOW] CWE-807 firefox: thunderbird: Mitigation bypass in the Data Loss Prevention component
firefox: thunderbird: Mitigation bypass in the Data Loss Prevention component
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Mitigation bypass in the Data Loss Prevention component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: thunderbird (Red Hat Enterprise Linux 6) - Out of support scope
Mozilla
Mozilla Foundation Security Advisory 2026-80: CVE-2026-74983
vendor_mozilla
CVE-2026-74983 Mozilla Foundation Security Advisory 2026-80: CVE-2026-74983
Mozilla Foundation Security Advisory 2026-80
CVE: CVE-2026-74983
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153.1
Mozilla
Mozilla Foundation Security Advisory 2026-74: CVE-2026-74983
vendor_mozilla
CVE-2026-74983 Mozilla Foundation Security Advisory 2026-74: CVE-2026-74983
Mozilla Foundation Security Advisory 2026-74
CVE: CVE-2026-74983
Product: Firefox
Impact: high
Fixed in: Firefox 154
Mozilla
Mozilla Foundation Security Advisory 2026-79: CVE-2026-74983
vendor_mozilla
CVE-2026-74983 Mozilla Foundation Security Advisory 2026-79: CVE-2026-74983
Mozilla Foundation Security Advisory 2026-79
CVE: CVE-2026-74983
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.14
Mozilla
Mozilla Foundation Security Advisory 2026-78: CVE-2026-74983
vendor_mozilla
CVE-2026-74983 Mozilla Foundation Security Advisory 2026-78: CVE-2026-74983
Mozilla Foundation Security Advisory 2026-78
CVE: CVE-2026-74983
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 154
Mozilla
Mozilla Foundation Security Advisory 2026-76: CVE-2026-74983
vendor_mozilla
CVE-2026-74983 Mozilla Foundation Security Advisory 2026-76: CVE-2026-74983
Mozilla Foundation Security Advisory 2026-76
CVE: CVE-2026-74983
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.14
Mozilla
Mozilla Foundation Security Advisory 2026-77: CVE-2026-74983
vendor_mozilla
CVE-2026-74983 Mozilla Foundation Security Advisory 2026-77: CVE-2026-74983
Mozilla Foundation Security Advisory 2026-77
CVE: CVE-2026-74983
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 153.1
GHSA
Mitigation bypass in the Data Loss Prevention component.
ghsa_unreviewed·2026-08-18
CVE-2026-74983 [HIGH] CWE-693 Mitigation bypass in the Data Loss Prevention component.
Mitigation bypass in the Data Loss Prevention component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2051897https://www.mozilla.org/security/advisories/mfsa2026-74/https://www.mozilla.org/security/advisories/mfsa2026-76/https://www.mozilla.org/security/advisories/mfsa2026-77/https://www.mozilla.org/security/advisories/mfsa2026-78/https://www.mozilla.org/security/advisories/mfsa2026-79/https://www.mozilla.org/security/advisories/mfsa2026-80/
2026-08-18
Published